Process and reactor for chemical recycling of plastic waste with alkane oxidation products

Abstract

1. A method for producing olefinic and aromatic hydrocarbons from waste plastics, comprising feeding a mixture of plastics with products of oxidation of light hydrocarbons to a process in which the feed mixture undergoes catalytic pyrolysis to produce olefins and aromatic compounds.

Description

[Technical Field]

[0001] Related Applications This application claims the benefit of priority to U.S. Provisional Patent Application No. 17 / 964,025, filed October 11, 2022.

[0002] The present disclosure relates to the conversion of waste plastics, polymers, and other waste materials into useful chemical and fuel products, such as paraffins, olefins, and aromatics, including feeding a mixture of plastics with light hydrocarbon oxidation products to a process in which the feed mixture undergoes catalytic anaerobic pyrolysis to produce olefins and aromatics.

[0003] Introduction According to a 2022 study by NREL (Milbrandt et al., "Quantification and evaluation of plastic waste in the United States," Resources, Conservation & Recycling, 183, August 2022), of the estimated 44 million tons of plastic waste managed in the United States in 2019, approximately 86% was landfilled, 9% was incinerated, and 5% was recycled. More than 368 million tons of plastic were produced worldwide. By some estimates, 8.3 billion tons of plastic have been produced, 6.3 billion tons have become waste, and only 9% of this has been recycled. Plastic recycling involves recovering scrap or waste plastic and reprocessing the materials into useful products. However, since China banned the import of waste plastic in 2018, the recycling rate in the United States is estimated to have fallen to just 4.4%.

[0004] Recycling plastics is difficult due to the chemical properties and low economic benefits of long-chain organic polymers. Furthermore, waste plastic materials often need to be separated into various types of plastic resins, such as low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene terephthalate (PET), for separate recycling processes. Pyrolysis and catalytic pyrolysis processes, in which waste plastics are heated to produce products such as liquid oil, gas, and carbon black, are well known.

[0005] Plas-TCat™ is a catalytic fluidized bed process that uses a zeolite catalyst to convert polymer / plastic materials, particularly waste plastics that may be destined for landfills or incinerators, into a mixture of permanent gases, C2-C4 light olefins, C1-C4 light paraffins, C5+ hydrocarbons (benzene, toluene, and xylenes (“BTX”)), aromatic and non-aromatic naphtha molecules, C11+ hydrocarbons, coke and char, and small amounts of by-products. Plastic mixtures with relatively high hydrogen to carbon molar ratios, such as polyethylene (PE), polypropylene, polystyrene, and combinations thereof, can be converted into olefins and aromatics.

[0006] Chemical plastic recycling plants have limited capacity and generate plastic waste over a wide area due to the limited amount of waste plastics that can be processed at any one location. This resource limitation puts them at an economic disadvantage compared to petroleum-based processes, which benefit from economies of scale where large amounts of equipment are available. This disclosure describes an integrated process that includes an alkane oxidation step that provides additional olefin and thermal energy to the catalytic pyrolysis of plastics, increasing the yield of BTX, olefins, or both. The combined process allows for closer integration of plastic recycling with traditional hydrocarbon upgrading facilities, i.e., multiple refineries, benefiting from both plastic reuse and refineries by introducing a means to create value from methane or light hydrocarbon mixtures beyond fuel. [Background technology]

[0007] Jones et al., in US 4,567,307, disclose a process for upgrading methane by contacting it with a reducing metal oxide to form ethylene, which is then catalytically oligomerized to form higher hydrocarbons. Gupta et al., in US 5,012,028, disclose a process for producing higher hydrocarbons by first oxidizing methane and then pyrolyzing the oxidation product in the presence of higher hydrocarbons separated from natural gas. US 5,336,825 (Choudhary) discloses a process for oxidizing methane to an ethylene-containing mixture and upgrading the ethylene mixture to higher hydrocarbons over a zeolite catalyst. US 6,596,912 (Lunsford et al.) discloses catalytic reaction of methane with O2 at 800°C to convert methane to ethylene, followed by catalytic oligomerization of the ethylene product over an H-ZSM-5 zeolite catalyst to produce C4+ products. In US 7,183,451 and US 7,667,085, Gattis et al. similarly describe processes for converting natural gas to higher hydrocarbons by oxidation and catalytic conversion of olefins to higher hydrocarbons. In US 8,710,286, Butter discloses reacting methane with oxygen to form ethane, processing the ethane to ethylene, and using the thermal energy generated in the plant. In US 10,793,490, Radaelli et al. disclose processes for upgrading the produced ethylene to higher hydrocarbons and various processes using methane oxidative coupling. In US 10,865,165, Nyce et al. describe a number of processes that utilize methane using the oxidative coupling of methane to produce ethylene, which is then converted into select higher hydrocarbon products. None of these disclosures describing methane upgrading include converting plastics into valuable chemicals.

[0008] Therefore, there is a need to increase the capacity and yield of chemical plastic recycling processes, as well as to create value from methane and other light hydrocarbons beyond fuel. This disclosure demonstrates how chemical plastic recycling can create a process that incorporates the oxidation of C1-C4 hydrocarbons to olefins, achieving higher mass yields of valuable materials such as olefins and aromatics than plastic pyrolysis alone. Summary of the Invention

[0009] The present invention provides a method for producing olefinic or aromatic hydrocarbons from waste plastics, comprising: feeding a stream comprising plastics to a catalytic pyrolysis reactor; reacting a stream comprising methane or ethane or an alkane having 1 to 4 carbon atoms with oxygen to produce a product stream comprising ethylene; passing at least a portion of the product stream from the alkane oxidation through the catalytic pyrolysis reactor; reacting the combined plastics and alkane oxidation product stream in the catalytic pyrolysis reactor at a temperature above 350°C to produce a vapor product; and recovering olefins, or aromatics, or some combination thereof from the vapor product.

[0010] In one embodiment, a mixture containing a polymer is converted along with the products of hydrocarbon oxidation in a fluidized bed catalytic pyrolysis process to produce olefins and aromatics.

[0011] In another aspect, the present invention provides a method for converting plastics to olefins, or aromatic compounds, or a mixture of olefins and aromatic compounds, comprising: feeding a stream comprising plastics to a catalytic pyrolysis reactor; reacting a stream comprising methane or ethane or a mixture of C1-C4 hydrocarbons with oxygen to produce a product stream comprising ethylene; pyrolyzing the plastics and at least a portion of the alkane oxidation products in the catalytic pyrolysis reactor at a temperature above 350°C to form a vapor product; and recovering olefins, aromatic compounds, or some combination thereof from the vapor product.

[0012] The present invention may further be characterized by one or any combination of the following features: providing a feed mixture comprising plastics to a catalytic pyrolysis reactor coupled with a catalyst; The feed mixture may be polyethylene (PE), polypropylene (PP), polystyrene (PS), polyester, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyvinyl dichloride (PVDC), acrylonitrile-butadiene-styrene (ABS) copolymer, polyamide, polyurethane, polyether, polycarbonate, poly(oxide), poly(sulfide), polyarylate, polyether ketone, polyetherimide, polysulfone, polyurethane, polyvinyl alcohol, and polymers produced by polymerization of monomers, dienes, olefins, styrene, acrylates, acrylonitrile, methyl methacrylate ... crosslinked polyurethanes; polyisocyanurates; crosslinked elastomers including, but not limited to, polyisoprene, polybutadiene, styrene-butadiene, styrene-isoprene, ethylene-propylene-diene monomer polymers, and mixtures thereof; the feed mixture comprises a waste plastic mixture selected from polyethylene terephthalate (PET), high density polyethylene (HDPE), polyvinyl chloride (PVC) or polyvinylidene (PVCD), low density polyethylene (LDPE), polypropylene (PP), polystyrene (PS), or mixed resins, or any combination thereof; the plastic feed mixture comprises waste plastic; The plastic feed mixture includes copolymers such as ethylene-propylene, EPDM, acrylonitrile-butadiene-styrene (ABS), nitrile rubber, natural and synthetic rubber, tires, styrene-butadiene, styrene-acrylonitrile, styrene-isoprene, styrene-maleic anhydride, ethylene-vinyl acetate, nylon 12 / 6 / 66, filled polymers, polymer composites, polymer composites with natural fibers, plastic alloys, other polymeric materials, and polymers or plastics dissolved in a solvent, or combinations thereof; the feed mixture can include materials obtained from polymer or plastic manufacturing processes as materials separated from waste streams, such as waste or discarded materials, post-consumer recycled polymer materials, municipal solid waste (MSW), black liquor, wood waste, or other biologically produced materials, or combinations thereof; reacting a stream comprising methane or ethane or a mixture of C1-C4 hydrocarbons with oxygen in an oxidation reactor to produce a product stream comprising ethylene; the feed mixture to the oxidation reactor comprises no more than 5, or 10, or 25, or 50, or 85% by volume of any one of CO, CO, N, He, or HO, or any combination thereof; passing at least a portion of the product from the alkane oxidation through a catalytic pyrolysis reactor; heat is recovered from the product stream of the alkane oxidation before a portion thereof is fed to the catalytic pyrolysis reactor; carrying out alkane oxidation in the presence of a catalyst; the oxidation reactor comprises a fixed bed or a fluidized bed reactor; the maximum temperature in the oxidation reactor is at least 500, or 600, or 700, or 800, or 850°C, or not more than 1000, or 950, or 900, or 850°C, or between 500 and 950, or between 600 and 900, or between 700 and 850°C; the residence time of the feed stream in the oxidation reactor is not more than 2, or 1, or 0.5, or 0.3, or 0.2, or from 0.01 to 2, or from 0.05 to 1, or from 0.2 to 0.5 seconds; the weight hourly space velocity of the feed gas to the oxidation reactor is at least 3,000, or 5,000, or 8,000, or 10,000, or 15,000 cm3 / g-cat-hr, or 3,000 to 25,000, or 0,000 to 15,000, or 8,000 to 12,000 cm3 / g-cat-hr; the feed to the oxidation reactor has an oxygen atom to carbon atom ratio of 1.2, 1.0, 0.9, 0.8, 0.7, 0.5 or less, or 0.3, or from 0.2 to 1.0, from 0.25 to 0.9, or from 0.3 to 0.7; At least a portion of the feed to the oxidation reactor comprises natural gas or biogas or methane derived therefrom; the catalytic pyrolysis reactor is a fluidized bed reactor; reacting the plastic and at least a portion of the products from the alkane oxidation in the presence of a catalyst in a fluidized bed catalytic reactor to form a product vapor mixture; the non-vapor products of the catalytic pyrolysis, or a portion of the gas remaining after removing the desired products, or both, are combusted to provide energy for the catalytic pyrolysis process; using a portion of the heat produced from alkane oxidation to heat the pyrolysis reactor or to heat the fluidization gas to the regenerator or as a heat source for other elements of the process; The catalytic pyrolysis reaction is carried out in a fluidized bed, circulating bed, bubbling bed, or riser reactor at an operating temperature in the range of 300°C to 800°C, 350°C to 750°C, 400°C to 700°C, 450°C to 650°C, or 500°C to 600°C; the superficial velocity of the gas stream within the fluidized bed catalytic pyrolysis reactor at its largest cross section is less than 1.0, 0.8, 0.7, 0.6, 0.5, 0.4, or 0.3 meters / second, or between 0.1 and 1.0, between 0.2 and 0.8, or between 0.4 and 0.7 meters / second; the absolute pressure in the catalytic pyrolysis reactor is at least 0.1 MPa (1 bara), or at least 0.3 MPa (3 bara), or at least 0.4 MPa (4 bara), or 0.1 to 2.0 MPa (1 to 20 bara), or 0.1 to 1.0 MPa (1 to 10 bara), or 0.3 to 0.8 MPa (3 to 8 bara), preferably 0.4 to 0.6 MPa (4 to 6 bara); the residence time of the vapor in the catalytic pyrolysis reactor is 0.5 seconds to 480 seconds, or 0.5 seconds to 240 seconds, or 2 seconds to 60 seconds, or 3 seconds to 30 seconds, or 4 seconds to 15 seconds; the catalyst is a solid catalyst, and the step of catalytic pyrolysis comprises pyrolyzing in a fluidized bed reactor in the presence of the solid catalyst to produce a fluid product stream and a spent catalyst comprising coke; the catalytic pyrolysis catalyst comprises a zeolite; the zeolite is at least partially in a protonated form, with the H+ ions replaced by at least some of the cations; The catalytic pyrolysis catalyst may be selected from natural zeolites, synthetic zeolites, and combinations thereof; the catalytic pyrolysis catalyst may be selected from ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-50, or a combination thereof; the catalytic pyrolysis catalyst comprises ZSM-5; The catalytic pyrolysis catalyst composition comprises a crystalline molecular sieve characterized by an SAR of greater than 12 and less than or equal to 240, and a CI of 5 to 10; the catalyst for catalytic pyrolysis in a fluidized bed comprises a catalytic molecular sieve, the catalytic molecular sieve comprising 30 to 90 wt. % or 40 to 70 wt. % of the composition of the catalyst particles; the catalyst for catalytic pyrolysis in the fluidized bed is in the form of fluidizable particulates; the product vapor mixture from the catalytic pyrolysis conversion comprises at least 20, or at least 30, or at least 50 wt. % olefins, in some embodiments in the range of 20 to 90 wt. % olefins; a mass yield of olefins in the product vapor mixture from the catalytic pyrolysis conversion based on the mass of the polymer feed of at least 30%, or at least 40%, or at least 45%, or at least 50%, or at least 55%, or at least 60%, or from 20% to 90%, or from 30% to 70%, or from 45% to 60%; a mass yield of BTX in the vapor product mixture from the catalytic pyrolysis reactor, based on the mass of the polymer feed, of at least 5%, at least 10%, or at least 20%, or at least 30%, or at least 35%, or at least 40%, or between 1% and 90%, between 5% and 70%, between 10% and 60%, or between 20% and 50% BTX; the mass yield of olefins and aromatics is greater than 40%, or greater than 60%, or greater than 70%, or greater than 75%, or greater than 80%, or between 40% and 99%, or between 60% and 95%, or between 65% and 90%, based on the mass of the solid hydrocarbonaceous material fed to the process, and the mass yield of all products is less than or equal to 100%, based on the mass of the solid hydrocarbonaceous material fed to the process; passing the vapor products of the catalytic pyrolysis through one or more solids separators comprising one or more cyclones; the product vapor mixture of catalytic pyrolysis comprises CH4 and C2-C4 paraffins; subjecting the product vapor mixture of catalytic pyrolysis to a separation process to produce a gas stream rich in CH4, CO, and H2, and sending at least a portion of said gas stream rich in CH4, CO, and H2 to said regenerator where it is combusted; sending the vapor products of the catalytic pyrolysis to a separation and recovery facility; a selectivity for ethylene as a percentage of total olefins produced of at least 20%, alternatively at least 25%, alternatively at least 30%, alternatively between 10% and 60%, alternatively between 20% and 45%, alternatively between 25% and 35%; a selectivity to propylene as a percentage of total olefins produced of at least 20%, alternatively at least 30%, alternatively at least 40%, alternatively at least 45%, alternatively at least 50%, alternatively between 20% and 70%, alternatively between 25% and 65%, alternatively between 28% and 55%; a mixture of benzene, toluene, xylene, or BTX is recovered from the product vapor mixture; recovering aromatics or olefins, or both, from the vapor product; recycling at least a portion of the recovered olefins to the catalytic pyrolysis reactor; recycling at least a portion of the recovered C1-C4 hydrocarbons to the oxidation reactor; at least a portion of the catalyst is recovered from the catalytic pyrolysis reactor and regenerated by reaction with air or oxygen or an oxidizing gas in a catalyst regenerator, and at least a portion of the regenerated catalyst is returned to the catalytic pyrolysis reactor; Heat from the catalyst regenerator is provided to the plastic feed or catalytic pyrolysis reactor; a thermally regenerated catalyst providing heat to the catalytic pyrolysis process; at least a portion of the catalytic pyrolysis catalyst recovered from the cyclone is fed to a catalyst regenerator; A portion of the energy produced in the catalyst regenerator can be used as thermal energy in the catalytic pyrolysis reactor or for product separation, or both, or the energy can be converted into electrical energy, or the energy produced can be used as thermal and electrical energy within the plant or can be exported, or a combination thereof; the net movement of catalyst through the catalyst regenerator is in an upward direction; feeding at least a portion of the products of the catalytic pyrolysis to a separation section of a steam cracker or hydrocracker facility; passing at least a portion of the product mixture from the catalytic pyrolysis through a separation train of a refinery or chemical plant; The steam cracker or hydrocracker is located within the refinery; carbon oxides or water, or both, are at least partially removed from the products of catalytic pyrolysis before the product mixture is passed to the separation section of the steam cracker or hydrocracker; removing solids from the product of catalytic pyrolysis so that the product vapor has a solids content of less than 10 mg / m3, or less than 5 mg / m3, or less than 2 mg / m3, or less than 1 mg / m3 of product vapor before the product vapor is fed to a steam cracker or hydrocracker; at least a portion of the methane separated in the steam cracker or hydrocracker separation train is fed to the oxidation reactor; methane or ethane or C1-C4 hydrocarbons separated in the separation section of the steam cracker or hydrocracker are fed to an oxidation reactor; olefins or aromatics or both are recovered from the separation section of the steam cracker or hydrocracker; the chlorine content of the steam stream fed to the steam cracker or hydrocracker is less than 50, or 20, or 10, or 5, or 3, or 2, or 1 ppmw, or between 0.1 and 50, or between 0.5 and 20, or between 1 and 5 ppmw; pre-treating the plastic feed mixture before feeding it to the catalytic pyrolysis reactor; drying the plastic feed mixture to achieve a moisture content of 20, or 10, or 5% moisture by weight or less; The plastic feed is comminuted to particles no larger than 40, 20, 10, 5, 2, or 1 mm in its longest dimension; Washing the plastic feed mixture with water, or an acid, or a base, or a sequence of two or more washes with one or more wash solutions; selectively removing at least a portion of the chlorine-containing plastics from the feed mixture; heating the plastic feed stream to at least 200°C to achieve a molten state and removing solids by filtration before feeding into a catalytic pyrolysis reactor; The plastic feed mixture is pretreated by pyrolysis in a pyrolysis reactor by anaerobic heating to a temperature of 250-300°C to at least partially decompose the polymer; the pretreatment pyrolysis reactor being one or more moving bed, single screw extruder, twin screw extruder, Auger reactor, rotary kiln reactor, or staged furnace grate reactor, or some combination thereof; the pretreatment pyrolysis reactor has an inlet port and an outlet port, the temperature at or near the inlet port can be 20°C to 150°C, for example, 20 to 100°C, or 20 to 50°C, and the temperature range at the hot outlet port can be 150°C to 300°C, for example, 200 to 275°C, or 225 to 250°C; the pretreatment pyrolysis reactor comprises two or more reactors in series; the residence time of the condensed phase in the pretreatment pyrolysis reactor, or in any reactor if more than one reactor is present, is at least 1, or at least 5, or at least 10, or at least 20, or at least 30 minutes, or from 1 to 60, or from 5 to 30, or from 10 to 30 minutes; wherein the plastic feed is heated in a pre-treatment pyrolysis reactor to a temperature greater than 150, 175, 200, or 225°C, or 100-350, 150-300, 150-275, or 150-250°C, vapors are removed, and the condensed phase is passed to a catalytic pyrolysis reactor or to a second pyrolysis reactor;

[0013] the chlorine content of the pretreatment pyrolysis reactor product is less than 50, or 20, or 10, or 5, or 2 ppmw, or between 0.1 and 50, or between 0.5 and 20, or between 1 and 5 ppmw; providing a solid co-reactant material to a pretreatment pyrolysis reactor; the solid co-reactant comprises one or more materials selected from agricultural lime, calcium oxide, calcium hydroxide, magnesium oxide, magnesium hydroxide, limestone, or hydrotalcite, or some combination thereof; a solid co-reactant material is separated from the products of the pretreatment pyrolysis and transferred to a co-reactant regenerator, where the carbonaceous material is reacted with air, and at least a portion of the hot solid co-reactant material is returned to the pyrolysis reactor; the product produced in the pretreatment pyrolysis reactor is transferred to a catalytic pyrolysis reactor containing a catalyst without cooling a majority of the product; Heat from the hot regenerated catalyst provides energy for any pretreatment processes; the oxidation reaction is carried out in an anaerobic reactor separate from the catalytic pyrolysis reactor; The oxidation reaction is carried out in a non-anaerobic reactor separate from the catalytic pyrolysis reactor, and the heat from the oxidation reaction is transferred to plastic pretreatment, catalytic pyrolysis, fluidization fluid, or used in a separation process, or some combination thereof.

[0014] In another aspect, the present invention provides a catalytic converter comprising one or more first conduits for receiving methane or ethane or a mixture of C1-C4 hydrocarbons, one or more second conduits for receiving an oxygen-containing gas, an optional entry port for adding a fluidizing fluid to the reactor downstream of the oxidation catalyst, a conduit or device for introducing a plastic-containing feed into a fluidized bed of catalytic pyrolysis catalyst, an exit port for passing the vapor product mixture of the catalytic pyrolysis through a separation train, a port for removing a portion of the fluidized bed catalyst, a catalyst regeneration system for reactivating the fluidized bed catalyst, and a conduit or device for introducing the regenerated catalyst into the fluidized bed. and an entry port for the first and second conduits, both of which feed a first section of a reactor, the first section of the reactor containing a catalyst for the oxidation of a stream containing methane or ethane or a mixture of C1-C4 hydrocarbons, and a second section of the reactor downstream of the first section, the second section containing a fluidized bed catalyst for the conversion of a stream containing plastics to olefins, aromatics, or a mixture of olefins and aromatics.

[0015] The reactor of the present invention may further be characterized by one or any combination of the following features: an adiabatic zone separating the first section of the reactor from the second section of the reactor; the second section of the reactor is above the first section of the reactor and the entire gas flow through the reactor is in an upward direction; The insulation zone is fitted with heat-absorbing or heat-reflecting insulation; a fluidizing fluid being introduced into the reactor after the first section of the reactor and before the second section of the reactor; the temperature of the fluidizing fluid entering the reactor is lower than the temperature of the product gas exiting the first section of the reactor; mixing the fluidizing fluid and the OCM product gas product streams in an adiabatic zone; the temperature of the gas mixture of OCM product gas and fluidizing fluid is less than 900, 850, 800, 750, 700, or 650°C; the relative volumetric flow rates of the fluidizing fluid and the OCM product gas stream can be in the range of 0.1:1 to 10:1, 0.5:1 to 5:1, or 1:1 to 3:1, or can be greater than 0.1:1, 0.3:1, or 1:1; the fluidizing fluid temperature upon entering the mixing zone may be less than 650, 550, 500, 450, 400, 300, or 200°C, or may be in the range of 100 to 650, 100 to 500, or 100 to 400°C; the mixing zone is fitted with distribution plate(s), baffles, beryl saddles, or other shaped objects, or some combination thereof; The fluidizing fluid can be injected into the mixing zone through one or more injection ports, which can be positioned tangentially, radially, or at intermediate angles to the axis of the reactor; the reactor is fitted with one or more distributor plates in the adiabatic or mixing zone that distribute the OCM product stream and any added fluidizing fluid to the catalytic pyrolysis zone through one or more ports; the ports in the distributor plate(s) may be sized and shaped to ensure that the superficial flow velocity of the gas mixture at the outlet of the port is greater than 1.0, 1.5, 2.0, 3.0, or 5.0 meters / second; the first section of the reactor comprising one or more lift pipes for mixing the fluidizing fluid and the OCM product stream prior to entering the catalytic pyrolysis portion of the reactor; one or more distributor plates, or ports in one or more lift pipes, each terminated with a cap that directs flow downward out of the port or pipe; the cross-sectional area of ​​any lift pipe is less than 30%, 30%, 25%, 20%, 15%, 10%, 5%, or 3%, or between 1% and 20%, or between 2% and 15%, or between 3% and 10% of the cross-sectional area of ​​the fluidized bed catalytic reaction zone; a catalyst drain is attached at or near the bottom of the fluidized catalyst bed to facilitate removal of a portion of the catalyst in a continuous manner; the reactor forms part of a reaction system that also includes a pretreatment pyrolysis reactor, or a catalyst regenerator, or both; an outlet conduit from the catalytic pyrolysis reactor feeding the product gas to one or more cyclones in which solids are separated, at least a portion of the solids being returned to the fluidized bed, and the remaining portion of the separated solids being discarded; the oxidation reaction is carried out in an anaerobic reactor separate from the catalytic pyrolysis reactor; The oxidation reaction is carried out in a non-anaerobic reactor separate from the catalytic pyrolysis reactor, and the heat from the oxidation reaction is transferred to plastic pretreatment, catalytic pyrolysis, fluidization fluid, or used in a separation process, or some combination thereof.

[0016] Chemically recycling plastics by pyrolyzing them in a catalytic pyrolysis reactor using the oxidation products of light alkanes has many advantages, including that all types of plastic mixtures are suitable; the long residence time in the catalytic pyrolysis reactor(s) ensures that the plastic pieces are heated to decomposition temperatures, eliminating the need to grind the plastic particles to small sizes; catalytic pyrolysis can operate at high temperatures; the vapor products from the alkane oxidation provide additional olefins to the catalytic pyrolysis reactor, increasing the yield of aromatics; and the ability to capture energy from the oxidation of light hydrocarbons for use in the process or to generate electricity. [Brief explanation of the drawings]

[0017] [Figure 1]A process is presented for converting mixed plastic materials into valuable products by catalytic pyrolysis of the mixed plastics with the vapor products of light alkane oxidation to produce olefins, aromatics, or some combination thereof. [Figure 2] 1 illustrates an embodiment of the present disclosure in which the plastics and alkane upgrading process is integrated with a steam cracker. [Figure 3] 1 represents another embodiment of the present disclosure in which the plastic mixture is first pretreated before being introduced into the catalytic pyrolysis reactor. [Figure 4] 1 shows a schematic diagram of the reactor configuration for the process of the present invention. [Figure 5] 1 shows a schematic diagram of a reactor configuration for the process of the present invention with a gas mixing zone. [Figure 6] 1 depicts a schematic diagram of a reactor configuration for the process of the present invention, including a distributor plate, which supplies mixed oxidation product gases and a fluidizing fluid to a catalytic pyrolysis bed. [Figure 7] 1 depicts a schematic diagram of a reactor configuration for the process of the present invention, including a lift pipe that mixes the oxidation product gas with a fluidizing fluid and feeds the mixture to a catalytic pyrolysis bed. [Figure 8] 1 depicts four different embodiments of the process with different recycling schemes. [Figure 9] Product flow rates (kg / s) calculated for a 500 tonne per day (tpd) plant for various PlasT-Cat configurations shown in Figure 4. [Figure 10] A comparison of olefin and aromatic yields (kg / s) calculated from various PlasT-Cat configurations shown in Figure 4 for a 500 tpd plant is shown. DETAILED DESCRIPTION OF THE INVENTION

[0018] Glossary With respect to aromatics, as used herein, the terms "aromatic" or "aromatic compound" are used to refer to a hydrocarbon compound or compounds that contain one or more aromatic groups, such as, for example, monoaromatic ring systems (e.g., benzyl, phenyl, etc.) and fused polycyclic aromatic ring systems (e.g., naphthyl, 1,2,3,4-tetrahydronaphthyl, etc.). Examples of aromatic compounds include, but are not limited to, benzene, toluene, indane, indene, 2-ethyltoluene, 3-ethyltoluene, 4-ethyltoluene, trimethylbenzene (e.g., 1,3,5-trimethylbenzene, 1,2,4-trimethylbenzene, 1,2,3-trimethylbenzene, etc.), ethylbenzene, styrene, cumene, methylbenzene, propylbenzene, xylene (e.g., p-xylene, m-xylene, o-xylene, etc.), naphthalene, methyl-naphthalene (e.g., 1-methylnaphthalene, anthracene, 9,10-dimethylanthracene, pyrene, phenanthrene, dimethyl-naphthalene (e.g., 1,5-dimethylnaphthalene, 1,6-dimethylnaphthalene, 2,5-dimethylnaphthalene, etc.), ethyl-naphthalene, hydrindene, methyl-hydrindene, dimethyl-hydrindene. In some embodiments, single-ring aromatic compounds and / or multi-ring aromatic compounds may also be produced.

[0019] With respect to fluids, the term "fluid" refers to a gas, a liquid, a mixture of a gas and a liquid, or a gas or liquid containing dispersed solids, liquid droplets, and / or bubbles. The terms "gas" and "vapor" have the same meaning and are sometimes used interchangeably. In some embodiments, it can be advantageous to control the residence time of the fluidizing fluid within the reactor. The fluidization residence time of the fluidizing fluid is defined as the volume of the reactor under process conditions of temperature and pressure divided by the volumetric flow rate of the fluidizing fluid.

[0020] Regarding fluidized bed reactors, the term "fluidized bed reactor" is given its conventional meaning in the art and is used to refer to a reactor that includes a vessel that can contain a particulate solid material (e.g., silica particles, catalyst particles, etc.), where a fluid (e.g., gas or liquid) passes through the particulate solid material at a velocity sufficient to suspend the solid material and cause it to behave as if it were a fluid. Examples of fluidized bed reactors are described in "Fluidization Engineering" by D. Kunii and O. Levenspiel, Butterworth-Heinemann, 1991, which is incorporated herein by reference. The term "circulating fluidized bed reactor" is also given its conventional meaning in the art and is used to refer to a fluidized bed reactor in which the particulate solid material exits the reactor, circulates through a line in fluid communication with the reactor, and is recycled back to the reactor. Examples of circulating fluidized bed reactors are described in "Fluidization Engineering" by D. Kunii and O. Levenspiel, Butterworth-Heinemann, 1991.

[0021] Bubbling fluidized bed reactors and turbulent fluidized bed reactors are also known to those skilled in the art. In bubbling fluidized bed reactors, the fluid stream used to fluidize the particulate solid material operates at a flow rate low enough that bubbles and voids are observed within the volume of the fluidized bed during operation. In turbulent fluidized bed reactors, the flow rate of the fluid stream is higher than that used in bubbling fluidized bed reactors, so that bubbles and voids are not observed within the volume of the fluidized bed during operation. Examples of bubbling and turbulent fluidized bed reactors are described in Kirk-Othmer Encyclopedia of Chemical Technology (online), Vol. 11, Hoboken, NJ: Wiley-Interscience, 2001, pages 791-825, which are incorporated herein by reference.

[0022] With respect to olefins, the terms "olefin" or "olefinic compound" (also known as "alkene") are given their ordinary meaning in the art and are used to refer to any unsaturated hydrocarbon containing one or more pairs of carbon atoms joined by a double bond. Olefins include both cyclic and acyclic (aliphatic) olefins, where the double bond is located between carbon atoms forming part of a cyclic (closed ring) or open-chain group, respectively. Furthermore, olefins can contain any suitable number of double bonds (e.g., monoolefins, diolefins, triolefins, etc.). Examples of olefinic compounds include, but are not limited to, ethene, propene, allene (propadiene), 1-butene, 2-butene, isobutene (2-methylpropene), butadiene, and isoprene, among others. Examples of cyclic olefins include cyclopentene, cyclohexane, and cycloheptene, among others. Aromatic compounds, such as toluene, are not considered olefins, but olefins containing aromatic moieties, such as benzyl acrylate or styrene, are considered olefins.

[0023] Regarding catalysts, catalytic components useful in the context of the present invention can be selected from any catalyst known in the art or understood by those skilled in the art. A catalyst promotes and / or influences a reaction. Thus, as used herein, a catalyst lowers the activation energy (increases the rate) of a chemical process and / or improves the distribution of products or intermediates in a chemical reaction (e.g., shape-selective catalysis). Examples of reactions that can be catalyzed include dehydration, dehydrogenation, isomerization, hydrogen transfer, hydrogenation, polymerization, cyclization, desulfurization, denitrogenation, deoxygenation, aromatization, decarbonylation, decarboxylation, aldol condensation, and combinations thereof. As will be understood by those skilled in the art, catalytic components can be considered acidic, neutral, or basic.

[0024] For catalytic pyrolysis, particularly advantageous catalysts include those containing internal porosity selected according to pore size (e.g., mesoporosity and microporosity typically associated with zeolites), e.g., average pore sizes of less than about 10 nm, less than about 5 nm, less than about 2 nm, less than about 1 nm, less than about 0.5 nm, or even smaller. In some embodiments, catalysts having average pore sizes of about 0.5 nm to about 10 nm can be used. In some embodiments, catalysts having average pore sizes of about 0.55 nm to about 0.65 nm, or about 0.59 nm to about 0.63 nm can be used. In some examples, catalysts having average pore sizes of about 0.7 nm to about 0.8 nm, or about 0.72 nm to about 0.78 nm can be used.

[0025] In some preferred embodiments of catalytic pyrolysis, the catalyst may be selected from natural zeolites, synthetic zeolites, and combinations thereof. In certain embodiments, the catalyst may be a ZSM-5 zeolite catalyst, as will be understood by those skilled in the art. In some cases, such catalysts may contain acidic sites. Other types of zeolite catalysts include ferrierite, zeolite Y, zeolite beta, mordenite, MCM-22, ZSM-23, ZSM-57, SUZ-4, EU-1, ZSM-11, (S)AlPO-31, and SSZ-23, among others. Zeolites and other small pore materials are often characterized by their constraint index. The constraint index approximates the ratio of the cracking rate constants for normal hexane and 3-methylpentane. A method for determining the constraint index is described in more detail in U.S. Pat. No. 4,029,716, the details of which are incorporated by reference. The zeolites referred to in this disclosure are, at least in part, those protonated forms in which the cations within the structure are at least in part replaced with H+ ions.

[0026] The Constraint Index (CI) values ​​of some representative materials are as follows: [Table 1]

[0027] The CI can vary within the indicated range of 1 to 12. Similarly, other variables, such as crystal size or the presence of potentially occluded exhaust contaminants and binders intimately associated with the crystals, can also affect the CI. Those skilled in the art will understand that the CI utilized herein, while providing a very useful means for characterizing the molecular sieves of interest, is approximate given the method of determination, and that extreme values ​​may be compounded in some cases. However, the CI will have a value within the approximate range of 1 to 12 for any given molecular sieve useful herein.

[0028] In other embodiments, non-zeolite catalysts such as WOx / ZrO2, aluminum phosphate, etc. may be used. In some embodiments, the catalyst may contain a metal and / or metal oxide. Suitable metals and / or oxides include, among others, nickel, palladium, platinum, titanium, vanadium, chromium, manganese, iron, cobalt, zinc, copper, gallium, and / or any of their oxides. In some examples, promoter elements selected from rare earth elements, i.e., elements 57-71, cerium, zirconium, or their oxides, or combinations thereof, may be included to modify the activity or structure of the catalyst. Furthermore, in some examples, the properties of the catalyst (e.g., pore structure, type and / or number of acid sites, etc.) may be selected to selectively produce desired products.

[0029] Oxidative coupling of methane, or OCM. Oxidative coupling of methane is a process in which two or more methane molecules are converted into higher hydrocarbons in the presence of an oxidizing agent. In this disclosure, the abbreviation OCM is used to refer to this process, as well as the oxidation of ethane, other C1-C4 hydrocarbons, or C1-C4 hydrocarbons, or combinations thereof.

[0030] With respect to plastics or polymers, the terms "plastic" and "polymer" are used interchangeably herein. A polymer is a carbon-based (at least 50 weight percent C) material composed primarily of repeating units and having a number average molecular weight of at least 100, usually greater than 1000, or even greater than 10,000. Polymers include thermoplastic polymers such as polyethylene, polypropylene, polyester, polyethylene terephthalate (PET), acrylonitrile-butadiene-styrene (ABS) copolymer, polyamide, polyurethane, polyether, polycarbonate, poly(oxide), poly(sulfide), polyarylate, polyetherketone, polyetherimide, polysulfone, polyurethane, polyvinyl alcohol, and polymers produced by polymerization of monomers such as dienes, olefins, styrene, acrylates, acrylonitrile, methacrylates ... Examples of suitable feedstocks include nitrile, diacids and diols, lactones, diacids and diamines, lactams, vinyl halides, vinyl esters, their block copolymers, and their alloys; thermosetting polymers such as epoxy resins, phenolic resins, melamine resins, alkyd resins, vinyl ester resins, unsaturated polyester resins, crosslinked polyurethanes, polyisocyanurates, and crosslinked elastomers, including, but not limited to, polyisoprene, polybutadiene, styrene-butadiene, styrene-isoprene, and ethylene-propylene-diene monomer polymers and blends thereof. Polymer mixtures separated from municipal solid waste or other waste streams are suitable feedstocks only if they contain only small amounts of contaminants such as S, N, O, or halogens. Polymers that produce halogenated materials upon pyrolysis, such as polyvinyl chloride (PVC), polytetrafluoroethylene (PTFE), and other halogenated polymers, are generally minimized or excluded from the feedstocks useful in this invention.

[0031] With respect to pyrolysis, the terms "pyrolysis" and "pyrolyzing" are given their conventional meanings in the art and are used to refer to the conversion of compounds, such as solid hydrocarbonaceous materials, by heat, preferably without the addition of or in the absence of O2, into one or more other substances, such as volatile organic compounds, gases, and coke. Preferably, the volume fraction of O2 present in the pyrolysis reaction chamber is 0.5% or less. Pyrolysis can occur with or without the use of a catalyst. "Catalytic pyrolysis" refers to pyrolysis carried out in the presence of a catalyst and can include steps described in more detail below. Examples of catalytic pyrolysis processes are outlined, for example, in Huber, G. Wet et al., "Synthesis of Transportation Fuels from Biomass: Chemistry, Catalysts, and Engineering," Chem. Rev. 106, (2006), pp. 4044-4098.

[0032] As used in this disclosure, the term "residence time" of a material in an apparatus or reactor can be calculated by dividing the volume of the apparatus or reactor by the volumetric feed rate of the feed material. For example, if the flow of fluidizing gas to a reactor is 5 SLPM (standard liters per minute) and the reactor volume is 2 liters, the residence time is 2 / 5 = 0.4 minutes at standard conditions. Residence time is often adjusted for reaction conditions by including expansion or contraction due to temperature differences. While this is important for gases, it is often not important and is therefore ignored for liquids and solids.

[0033] Regarding selectivity, the term "selectivity" refers to the amount of a specific product produced compared to a selected product. The selectivity for a product can be calculated by dividing the amount of a specific product by the amount of several products produced. For example, if a reaction produces 75 grams of aromatic compounds and 20 grams of benzene is detected among those aromatic compounds, the selectivity to benzene among the aromatic products is 20 / 75 = 26.7%. Selectivity can be calculated on a mass basis, as in the previous example, or on a carbon basis, where selectivity is calculated by dividing the amount of carbon in a specific product by the amount of carbon in a selected product. Unless otherwise specified, for reactions involving polymers as reactants, selectivity is on a mass basis. For reactions involving the conversion of a specific molecular reactant (such as ethene), selectivity is the percentage (mass basis unless otherwise specified) of the selected product divided by all products produced.

[0034] Regarding yield, the term "yield" herein refers to the amount of product leaving the reactor divided by the amount of reactants entering the reactor, typically expressed as a percentage or fraction. Yields are often calculated on a mass basis, a carbon basis, or based on specific feed components. Mass yield is the mass of a specific product divided by the mass of the feed used to prepare that product. For example, if 500 grams of polymer are fed to a reactor and 45 grams of benzene are produced, the mass yield of benzene is 45 / 500 = 9% benzene. Carbon yield is the mass of carbon in a specific product divided by the mass of carbon in the reactor feed. For example, if 500 grams of a polymer containing 90% carbon are reacted to produce 400 grams of benzene containing 92.3% carbon, the carbon yield is [(400 * 0.923) / (500 * 0.90)] = 82.0%.

[0035] As in standard patent terminology, the term "comprising" means "including" and does not exclude additional components. Any aspect of the invention described in connection with the term "comprising" also includes narrower embodiments in which the term "comprising" is replaced with the narrower terms "consisting essentially of" or "consisting of." As used herein, the terms "includes" or "including" should not be construed as limiting the invention, but rather as listing exemplary components.

[0036] Detailed Description of the Invention Creating value from waste streams is becoming more urgent as the world strives to develop a circular economy designed to minimize resource inputs as well as the generation of waste and emissions. A circular economy aims to achieve limited resource use, a gradual transition to renewable resources, and maximized efficiency in the recovery of materials and products at the end of their useful life. The disclosed process enables a circular economy by recovering value in waste plastics and light hydrocarbons. The disclosed process involves catalytic pyrolysis of a mixture of waste plastics to which methane or other light hydrocarbon partial oxidation products have been added.

[0037] Creating value from methane through upgrading processes has long been a goal of the chemical and petroleum industries. Despite extensive research, oxidative methane coupling to produce C2+ hydrocarbons has not become a stand-alone commercial process due to fundamental limitations in its chemistry. The reaction is a radical reaction, in which the products ethane and ethylene are nearly as susceptible to transformation as methane. A maximum yield is reached, beyond which product destruction exceeds product formation. The maximum yield is approximately 35% (Bhatia, S., et al., "Oxidative coupling of methane (OCM) in a catalytic membrane reactor and comparison of its performance with other catalytic reactors," Chem Eng. J., 148(2-3), 2009, 525-532), far below the approximately 65% ​​yield required to support a stand-alone process. The low yield and high cost of separating the C2+ products from the product mixture contribute to the high cost of the process.

[0038] The present disclosure integrates the oxidative coupling of methane with the catalytic pyrolysis of plastics, and provides a process that utilizes the olefins and heat produced in the oxidative coupling to efficiently 1) provide the heat required for catalytic pyrolysis, 2) increase the yield of aromatics and olefins from catalytic pyrolysis, and 3) can take advantage of economies of scale available with large-capacity product separation facilities, such as those associated with existing steam crackers or hydrocrackers.

[0039] Figure 1 depicts a conceptual embodiment of a process for converting mixed plastic materials into valuable products by catalytic pyrolysis of the mixed plastics with vapor products of light alkane oxidation to produce olefins, aromatics, or some combination thereof. The plastic mixture is introduced into a catalytic fluidized-bed reactor (PlasT-Cat™) equipped with a catalytic pyrolysis catalyst to convert the polymers into olefins, alkanes, and aromatics. Methane or a mixture of light C1-C4 hydrocarbons is introduced into a partial oxidation reactor containing an oxidant such as O2 or air. In the oxidation reactor (OCM, oxidative coupling of methane), methane or mixed hydrocarbons react in the presence of an oxidative coupling catalyst (OCM catalyst) to form ethylene and C2+ hydrocarbons, including COx and sulphur. The hot gaseous product mixture is fed to a catalytic pyrolysis reactor, which provides heat to raise the temperature of the mixture to a temperature where the polymers crack and react in the presence of the catalyst to form olefins, aromatics, and alkanes. The products of catalytic pyrolysis pass through a separation train to recover BTX (benzene, toluene, xylenes), olefins, and other useful products. A portion of the methane or other light alkanes separated in the separation train can be used as feed to the oxidation reactor, or methane from sources such as natural gas or biogas can be used. Coke or other materials that build up on the catalyst are recovered by passing at least a portion of the pyrolysis catalyst through a catalyst regenerator where the material is oxidized with air or other oxygen-containing gas to remove carbonaceous deposits and restore catalytic activity. At least a portion of the regenerated catalyst is returned to the fluidized-bed PlasT-Cat™ reactor.

[0040] Figure 2 shows an embodiment of the present disclosure in which the plastics and alkane upgrading process is integrated with a steam cracker. In this configuration, the product of the PlasT-Cat™ reactor is passed through the separation system of the steam cracker. Aromatics (BTX), olefins, and alkanes can be recovered from the separation system, and a portion of the alkanes can be returned to the steam cracker for further processing. A portion of the methane or light hydrocarbon mixture can be fed to an oxidation reactor for conversion to additional ethylene and other products. Methane from an external source can optionally be added to the feed to the oxidation reactor. In this embodiment, a portion of the cracked plastics and light hydrocarbons can be introduced into an existing steam destruction facility to increase the production of chemicals or fuels.

[0041] 3 depicts another embodiment of the present disclosure in which the plastic mixture is first pretreated before being introduced into the PlasT-Cat™ reactor. Pretreatment of the plastic mixture can remove chlorine-containing materials by removing HCl, or by melting the plastic to allow separation of solids from the plastic, or by washing the plastic to remove impurities such as salts, metals, mineral matter, or dust, or otherwise preparing the plastic mixture for processing by PlasT-Cat™.

[0042] Suitable feed materials for use in the present invention include polyethylene (PE), polypropylene (PP), polyacetylene, polybutylene, polyolefin, polyethylene terephthalate (PET), polybutylene terephthalate, polyester, copolyester, polycarbonate, polyurethane, polyamide, polystyrene. (PS), polyacetal, epoxy, polycyanurate, polyacrylic acid, polyurea, vinyl ester, polyacrylonitrile, polyamide, polyurethane, polyether, polycarbonate, poly(oxide), poly(sulfide), polyarylate, polyether ketone, polyetherimide, polysulfone, polyurethane, polyvinyl alcohol, polyvinyl chloride (PVC), polyvinyl dichloride (PVDC), polyvinyl acetate, nylon, copolymers such as ethylene-propylene, acrylonitrile-butadiene-styrene (ABS), nitrile rubber, natural and synthetic rubber, tires, styrene-butadiene, styrene-acrylonitrile, styrene-isoprene, styrene-maleic anhydride, ethylene vinyl acetate, nylon 12 / 6 / 66, filled polymers, polymer composites, plastic alloys, other polymeric materials, and polymers or plastics dissolved in solvents (including waste or discarded materials). The polymeric material may include all types of polymeric materials, including polymers produced by polymerization of monomers such as dienes, olefins, styrenes, acrylates, acrylonitrile, methacrylates, methacrylonitrile, diacids and diols, lactones, diacids and diamines, lactams, vinyl esters, block copolymers thereof, and alloys thereof, thermosetting polymers such as epoxy resins, phenolic resins, melamine resins, alkyd resins, vinyl ester resins, unsaturated polyester resins, crosslinked polyurethanes, polyisocyanurates, and crosslinked elastomers, including, but not limited to, polyisoprene, polybutadiene, styrene-butadiene, styrene-isoprene, or any combination thereof.The present invention includes combinations of these materials as needed or available from a particular location, and the invention can be described as including one or any combination of these materials.

[0043] In either method, the catalytic pyrolysis reactor can be a fluidized-bed reactor in which the catalyst is a solid catalyst, and the catalytic pyrolysis process includes pyrolysis in the fluidized-bed reactor in the presence of the solid catalyst to produce a fluid product stream and coke-containing spent catalyst, where at least a portion of the carbon in the feed is converted to coke and volatile products. In either method, vapors exiting the catalytic pyrolysis reactor can be passed through an optional solids separation device, such as a cyclone or screen, to remove entrained solids. In either method, at least a portion of the coke-containing spent catalyst is transferred to a regenerator where the coke reacts with oxygen or air to form hot regenerated catalyst, and at least a portion of the hot regenerated catalyst is returned to the fluidized-bed reactor where heat from the hot regenerated catalyst provides energy for the pyrolysis process.

[0044] In either method, the catalytic pyrolysis step can include pyrolysis in the presence of a fluidized bed catalyst. The catalytic pyrolysis reactor can include a fluidized bed, circulating bed, bubbling bed, or riser reactor operating at temperatures ranging from 300°C to 800°C, or 350°C to 750°C, or 400°C to 700°C, or 450°C to 650°C, or 500°C to 600°C. The vapor residence time in the catalytic pyrolysis can be from 1 second to 480 seconds, or from 1 second to 240 seconds, or from 2 seconds to 60 seconds, or from 3 seconds to 30 seconds, or from 4 seconds to 15 seconds. The pressure in the catalytic pyrolysis reactor may be at least 0.1 MPa (1 bar), or at least 0.3 MPa (3 bar), or at least 0.4 MPa (4 bar), or from 0.1 to 2.0 MPa (1 to 20 bar), or from 0.1 to 1.0 MPa (1 to 10 bar), or from 0.3 to 0.8 MPa (3 to 8 bar), preferably from 0.4 to 0.6 MPa (4 to 6 bar), the pressure being absolute.

[0045] The design and conditions of the fluidized bed reactor may be those known in the art. A fluidizing gas may be required at start-up, and during steady-state operation, the fluidizing gas may comprise part of the vapor stream and may optionally be piped to the bottom of the fast catalytic pyrolysis fluidized bed reactor. Recycle gas from the process may be used as the fluidizing gas, or at least a portion of the product gas from the oxidation reactor may be used as a component of the fluidizing gas.

[0046] For catalytic pyrolysis, useful catalysts include catalysts with internal porosity selected according to pore size (e.g., mesoporosity and microporosity typically associated with zeolites), e.g., average pore sizes of less than 10 nm, less than 5 nm, less than 2 nm, less than 1 nm, less than 0.5 nm, or even smaller. In some embodiments, catalysts with average pore sizes of 0.5 to 10 nm can be used. In some embodiments, catalysts with average pore sizes of 0.5 to 0.65 nm, or 0.59 to 0.63 nm can be used. In some examples, catalysts with average pore sizes of 0.7 to 0.8 nm, or 0.72 to 0.78 nm can be used.

[0047] Particularly advantageous catalyst compositions for the catalytic pyrolysis fluidized-bed reactor of the present invention include crystalline molecular sieves characterized by an SAR (silica to alumina, SiO:AlO mass ratio) greater than 12, or from 12 to 240, and a CI (constraint index) of 1 to 12. Non-limiting examples of such crystalline molecular sieves include those having the structure of ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-50, or combinations thereof. In one embodiment, the catalyst composition includes a crystalline molecular sieve characterized by an SAR greater than 12 to 240 and a CI of 5 to 10, such as a molecular sieve having the structure of ZSM-5, ZSM-11, ZSM-22, ZSM-23, or combinations thereof. Methods for determining CI are more fully described in U.S. Pat. No. 4,029,716, the details of which are incorporated herein by reference.

[0048] The molecular sieve used herein or a catalyst composition containing the same may be heat-treated at elevated temperatures. This heat treatment is generally carried out by heating at a temperature of at least 370°C for at least 1 minute, generally for up to 20 hours (usually in an oxygen-containing atmosphere, preferably air). Although subatmospheric pressures may be used for the heat treatment, atmospheric pressure is preferred for convenience. Heat treatment may be carried out at temperatures up to about 925°C. Heat-treated products are particularly useful in the process of the present invention.

[0049] For the catalyst compositions useful in the present invention, suitable molecular sieves can be used in combination with a carrier or binder material, such as a porous inorganic oxide carrier or a clay binder. Non-limiting examples of such binder materials include alumina, zirconia, silica, magnesia, thoria, titania, boria, and combinations thereof, typically in the form of dry inorganic oxide gels and gelatinous precipitates. Suitable clay materials include, by way of example, bentonite, diatomaceous earth, and combinations thereof. The relative proportion of suitable crystalline molecular sieves in the overall catalyst composition can vary widely, with molecular sieve content ranging from 30 to 90 weight percent of the composition, more typically from 40 to 70 weight percent. The catalyst composition can be in the form of extrudates, beads, or fluidized microspheres.

[0050] The molecular sieves used herein or catalyst compositions containing same may have their original cations at least partially replaced by ion exchange with hydrogen, or hydrogen precursor cations, or non-noble metal ions of Group VIII of the Periodic Table, i.e., nickel, iron, or cobalt, or zinc, or gallium, or combinations thereof, according to techniques well known in the art.

[0051] In either method, the vapors exiting the catalytic pyrolysis reactor can be passed through an optional solids separation device, such as one or more cyclones or screens, to remove entrained solids. The solid mixture containing the deactivated catalyst can contain residual carbon and / or coke, as well as coke or char from the process, which can be removed by reaction with an oxidizing agent in a regenerator. In either method, the catalyst can be removed from the catalytic pyrolysis reactor and sent to a catalyst regenerator, where it is reacted with an oxygen-containing gas, and the regenerated catalyst can be returned to the catalytic pyrolysis reactor. The oxygen-containing gas can come from any source, including, for example, oxygen, atmospheric air, steam, etc. In the regenerator, the catalyst reacts with the oxidizing agent to reactivate the catalyst and generate heat. In some embodiments, a portion of the gaseous products from the catalytic pyrolysis process is fed to a catalyst regenerator and combusted with the solid materials. The gaseous products can first be separated into an olefin-rich stream and an olefin-lean stream, and at least a portion of the olefin-lean stream can be fed to a catalyst regenerator. In the process of regenerating catalysts obtained from catalytic pyrolysis, the heat generated by the oxidation of coke, char and other materials in the catalyst regenerator can be used elsewhere in the process or converted into electricity for export.

[0052] In some embodiments, for example, when using recycled polymeric materials, impurities can optionally be removed from the feed composition before it is fed to the catalytic pyrolysis reactor by an optional pretreatment step, such as in Figure 3. In either method where the feed is pretreated and impurities are removed by washing, the wash solution or solutions can be acidic, basic, or near-neutral. The wash sequence can include a single contact with a wash solution or multiple contacts with wash solutions, and the wash solutions can be different at various steps in the wash sequence. Washing can be carried out in a countercurrent mode or in a series of batch contact reactors.

[0053] In some cases, the pretreatment step may include mechanical separation, sink / float separation, air sieving, or other known separation processes, preferably in an automated mode. In some examples, the particle size of the solid polymer feed composition can be reduced in a size reduction system before sending the feed to the pyrolysis reactor. In some embodiments, the average diameter of the reduced-size feed composition exiting the size reduction system comprises about 50% or less, about 25% or less, about 10% or less, about 5% or less, or about 2% or less of the mass average diameter of the feed composition fed to the size reduction system. The feed mixture can include a plastic mixture in which at least 85%, or at least 90%, or at least 95% by mass of the particles pass through a 0.25-inch (0.6 cm), or 0.5-inch (1.2 cm), or 1.0-inch (2.5 cm), or 1.5-inch (3.7 cm), or 2-inch (5.0 cm), or 4-inch (10.0 cm) screen. The average diameter (size) can be measured through a mesh (sieve). Large particle feed materials may be easier to transport and less difficult to process than small particle feed materials. On the other hand, in some cases it may be advantageous to feed small particles to the reactor. The use of a size reduction system allows for the transport of large particle feed between the source and the process while simultaneously allowing for the feeding of small particles to the reactor.

[0054] In any method in which the feed is pretreated in one or more pyrolysis reactors, any of the pretreatment pyrolysis reactors can be a moving-bed reactor, in which the feed is propelled along the length of the reactor by mechanical, gravitational, or both mechanical and gravitational means. Typical examples of reactors suitable for the pyrolysis reactor include single-screw extruders, twin-screw extruders, Auger reactors, rotary kiln reactors, or tray grate reactors. In any embodiment, the pyrolysis reactor can be equipped with a means for separating condensable materials, such as solids and / or liquids, from the vapor product and with a condensed phase outlet separate from the vapor phase outlet. In any embodiment, the pyrolysis reactor has multiple heating zones, with successively higher temperatures in subsequent zones. In some embodiments, the pyrolysis reactor is equipped with a gas outlet in a region of the reactor where the temperature of the material in the reactor is below 300°C or between 250°C and 300°C so that products produced at lower temperatures, such as steam, HCl, NH3, or other materials, can be removed from the reactor. In one embodiment, a separation barrier is installed in the pyrolysis reactor immediately downstream of the gas outlet to at least partially prevent gases evolved at lower temperatures from entering the hotter section of the reactor along with molten and solid materials. In either method where the feed is pretreated in one or more reactors, at least a portion of the energy required for pyrolysis can be provided by a slipstream of products from the hydrocarbon oxidation (OCM) reactor or by heat exchange with hot products from the OCM reactor.

[0055] When an Auger pretreatment pyrolysis reactor is utilized, embodiments of the present invention include a spiral auger, optionally with different pitch dimensions in different portions of the auger, to tailor the velocity of the condensed phase from the inlet to the outlet of the reactor. In this embodiment, the flight thickness and shaft diameter may also be variable along the length of the auger to control the flow rates of the vapor and condensed phases. Augers with paddled, cut, or folded flights are also contemplated within the scope of these embodiments.

[0056] In embodiments, when a rotary kiln pretreatment pyrolysis reactor is utilized, the kiln cylinder can be fitted with lifters, such as spiral lifters attached to the cylinder wall, or plate-like lifters, folded lifters, or segmented lifters extending from the cylinder wall. The rotary kiln reactors contemplated herein can also be tilted either up or down toward the exit end of the kiln, depending on the desired residence time and flow rate of the condensed phase within the kiln, thus utilizing gravity to control the residence time of the condensed phase. It is also contemplated that the rotational speed of the rotary kiln reactor can be adjusted as desired, for example, between 20 revolutions per minute and 0.2 revolutions per minute, depending on the nature of the feed mixture and added co-reactants, to provide thorough mixing and high heat transfer. The rotary kiln reactors contemplated in these embodiments can be externally heated by combustion of process waste gases, such as CH4, C2-C4 paraffins, H2, and CO, recycled from product separations or natural gas, or electrically.

[0057] In either embodiment, the temperature profile within the pretreatment pyrolysis reactor ranges from a low temperature near the feed inlet port to a high temperature at the outlet port or ports. The temperature range within the pretreatment pyrolysis reactor can be 20°C to 150°C, e.g., 20-100°C, or 20-50°C, and the temperature range at the high temperature outlet port can be 150°C to 300°C, e.g., 200-275°C, or 225-250°C.

[0058] In embodiments where solid co-reactant material is fed to the pretreatment pyrolysis reactor, the solid co-reactant material is optionally transferred to a combustion regenerator where the carbonaceous material reacts with air and at least a portion of the hot solid co-reactant material is returned to the pyrolysis reactor. In one embodiment of the present invention, the hot flue gas exiting the solid co-reactant regenerator is sent to a catalytic heater to heat the catalyst in the catalytic pyrolysis reactor.

[0059] Methane, ethane, or mixed C1-C4 hydrocarbon oxidation processes are exothermic and are typically carried out at higher temperatures than catalytic pyrolysis processes, which are endothermic. Product streams from methane coupling (OCM) or hydrocarbon oxidation processes are often at temperatures above 800°C, 850°C, 900°C, or even 950°C, while catalytic pyrolysis catalysts can be damaged by exposure to temperatures above about 650°C. Therefore, when hydrocarbon oxidation and catalytic pyrolysis processes are carried out in a single reactor, the reactor may need to be designed so that the catalytic pyrolysis catalyst is not exposed to the higher temperature hydrocarbon oxidation product stream.

[0060] This can be achieved by including an adiabatic zone between the hydrocarbon oxidation catalyst and the catalytic pyrolysis catalyst, as shown schematically in Figure 4. The adiabatic zone can be fitted with insulating material that absorbs or reflects heat radiation and prevents it from reaching the catalyst located in the catalytic pyrolysis zone, or the adiabatic zone can be fitted with means for removing heat from the fluid, or the adiabatic zone can be an empty tube.

[0061] One option for reducing the temperature of the hydrocarbon oxidation product gas stream before it reaches the catalytic pyrolysis catalyst is to mix additional fluidizing fluid into the product stream by injecting the fluidizing fluid into a mixing zone where the hotter oxidation product stream and the cooler fluidizing fluid mix to produce a mixture having a temperature suitable for injection into the catalytic pyrolysis bed, as shown in Figure 5. The mixing zone can be fitted with any of a wide range of mixing devices, such as distribution plate(s), baffles, beryl saddles, or other shaped objects, or some combination thereof. The fluidizing fluid can be injected into the mixing zone through one or more input ports, which can be positioned tangentially, radially, or at intermediate angles to the reactor axis, to promote rapid mixing of the fluidizing fluid and the oxidation product gas stream.

[0062] Above the oxidation catalyst, the reactor can be fitted with one or more distributor plates that distribute the oxidation product stream and any added fluidization fluid to the catalytic pyrolysis zone through one or more ports, as shown in Figure 6. The ports in the distributor plate(s) can be sized and shaped to ensure that the superficial flow velocity of the gas mixture at the port outlet is greater than 1.0, 1.5, 2.0, 3.0, or 5.0 meters / second, minimizing catalyst ingress into the ports and mixing zone. Optionally, each port can be capped with a cap that directs the flow exiting the port downward, preventing catalyst from ingress into the mixing zone.

[0063] In some embodiments, the reactor can include one or more lift pipes, as shown in Figure 7, which serve to mix the fluidization fluid and oxidation product streams before they enter the catalytic pyrolysis section. In this embodiment, the entry ports are capped with caps that deflect the mixed gas flow downward and prevent catalyst from migrating into the mixing zone. In this embodiment, the cross section of any lift pipe is less than 30%, 30%, 25%, 20%, 15%, 10%, 5%, or 3%, or between 1% and 20%, or between 2% and 15%, or between 3% and 10% of the cross section of the fluidized-bed catalytic reaction zone, allowing for easier mixing of the fluids within the lift pipe and allowing the superficial velocity of the gas mixture within the catalytic pyrolysis zone to be maintained below the superficial velocity at which the catalyst is easily transported out of the reactor, i.e., below the velocity at which a bubbling bed can be maintained without undesirable catalyst loss. In some embodiments, the superficial velocity of the mixed gas flow within the fluidized bed at the largest cross section is less than 1.0, 0.8, 0.7, 0.6, 0.5, 0.4, or 0.3 meters / second, or between 0.1 and 1.0, 0.2 and 0.8, or 0.4 and 0.7 meters / second.

[0064] 5, 6, and 7, where the fluidizing fluid is introduced after the hydrocarbon oxidation catalyst zone, the relative volumetric flow rates of the fluidizing fluid and the oxidation product gas stream can be in the range of 0.1:1 to 10:1, 0.5:1 to 5:1, or 1:1 to 3:1 necessary to produce a gas mixture having a temperature less than 900, 850, 800, 750, 700, or 650° C., or can be greater than 0.1:1, 0.3:1, or 1:1. The fluidizing fluid temperature upon entering the mixing zone can be less than 650, 550, 500, 450, 400, 300, or 200° C., or in the range of 100 to 650, 100 to 500, or 100° C. to 400° C.

[0065] A catalyst drain is attached at or near the bottom of the fluidized catalyst bed to facilitate removal of a portion of the catalyst in a continuous manner. The removed catalyst is sent to a catalyst regenerator or a portion is discarded. Any of the reactors of Figures 4, 5, 6, or 7 may be fitted with an outlet conduit from a catalytic pyrolysis reactor (not shown) that feeds product gases to one or more cyclones in which solids are separated, at least a portion of the solids are returned to the fluidized bed, and the remaining portion of the separated solids are discarded.

[0066] In other embodiments of the present invention, the oxidation reaction may be carried out in a reactor separate from the catalytic pyrolysis. In some embodiments, the oxidation reactor may be an adiabatic reactor in which the gas mixture is heated by released energy. In other embodiments, the oxidation reactor is non-adiabatic, i.e., heat is released from the oxidation reactor. In these cases, the oxidation reactor may be configured to allow the energy of oxidation to be passed to another unit operation, such as plastic pretreatment, catalytic pyrolysis, or product separation. [Example]

[0067] The calculated performance of the proposed configuration was compared with that of a direct-pass Plas-TCat™, shown in Figure 8. In Figure 8, scheme (A) shows a direct-pass process consisting of a catalytic pyrolysis reactor (Plas-TCat™), whose products enter a separation section to separate alkanes, BTX, and olefins. Scheme (B) shows a configuration in which an olefin-rich stream is separated from the reactor effluent and recycled back to the pyrolysis reactor. Schemes (C) and (D) show two possible configurations for the integration of an alkane oxidation (OCM) process into the system.

[0068] The performance of the alkane oxidation reactor was determined based on literature experimental data from Mleczko, L., Gayko, G., Niemi, VM, & Hiltunen, J. (1997, "Reaction engineering studies in a polytropic fixed-bed reactor over a highly active and selective catalyst for oxidative methane coupling", Chemical Engineering & Technology: Industrial Chemistry‐Plant Equipment‐Process Engineering‐Biotechnology, 20(1), 29-35), where the following parameters were defined: inlet CH4 to O2 ratio = 2.2, O2 conversion = 98.3%, CH4 conversion = 40.8%, carbon selectivity to C2+ hydrocarbons = 52.5%, ratio of olefinic C2 products to paraffinic C2 products = 1.21, hydrogen yield = -1.9 wt%, and C2+ hydrocarbon yield = 21.4 wt%. The alkane oxidation reactor was set at operating conditions of 840 °C and 4 bar. Based on experimental data reported by Zavyalova, Ulyana, et al., "Statistical analysis of past catalytic data on oxidative methane coupling for new insights into the composition of high-performance catalysts," ChemCatChem 3.12 (2011): 1935-1947, a 20% decrease in C2+ selectivity was included as a correction factor to account for operation at 4 bar.

[0069] Based on these parameters, a mass balance around the hydrocarbon oxidation (OCM) reactor was performed for base case Scheme A, as summarized in Table 2. Configurations without alkane oxidation (A and B) were compared to configurations with alkane oxidation (C and D) based on the expected changes in olefin and aromatics product yields, as well as the effect of the heat balance of the Plas-TCat™ reactor and catalyst regenerator.

[0070] To investigate the impact on overall process yield, the kinetic behavior of the PlasT-Cat reactor must be evaluated in two cases. The performance of the PlasT-Cat reactor is investigated using a fluidized-bed model that combines both hydrodynamic and kinetic behavior. The model is a compartmentalized model that has been extensively discussed in the literature and widely applied by practitioners in this field. Details of such models are detailed in many sources, such as Kato, K., and C.Y. Wen. "Bubble assemblage model for fluidized bed catalytic reactors." Chemical Engineering Science 24.8 (1969): 1351-1369. The premise of this model is to capture the variability in hydrodynamic behavior and species composition at various inlet points of a multiphase fluidized-bed reactor. The variability of these characteristics is captured by dividing the reactor axially into compartments, with the height of each compartment equal to the average bubble size at that axial distance from the distributor. Each compartment consists of two or three phases, typically a foam phase, an emulsion phase, and a cloud phase. The foam phase represents the volume of species present as bubbles and is used primarily to capture the hydrodynamic behavior of the fluidized bed. The emulsion phase consists of species present outside the foam phase and is used to capture non-hydrodynamic behavior, such as mass and heat transfer and reaction kinetics. Exchange between phases occurs through bubble coalescence and breakup along the reactor axis. In some cases, an additional cloud phase is included. This cloud phase is primarily used to represent mass transfer as an interaction region between two other phases. Each compartment is then modeled as a perfectly mixed reactor, with exchanges occurring within subsequent compartments due to mass transfer, bubble coalescence / breakup, and reaction events. Such a model was developed to represent the Plas-TCat reactor. Hydrodynamic phases were obtained from the literature to represent bubble growth, bubble coalescence, and breakup, as well as mass exchange rates, while an empirical lumped kinetic model was used to represent reaction kinetics. The kinetic model was developed based on a large-scale experimental program to measure the catalytic pyrolysis performance of the Plas-TCat system.

[0071] The Plas-TCat™ reactor modeled in this example was operated at 570°C and 4 bar pressure, with an inlet fluidization velocity of 0.15 m / s and a reactor H / D ratio ranging from 1 to 2. In the single-pass case, the composition of the fluidization gas into the reactor was considered inert. In the olefin recycle case, the recycle gas composition was 3.3% CO, 8.8% CO, 2.73% H, 15.82% H, 15.82% nitrogen, 0.88% water, 7.67% paraffins, and 60.8% olefins, which were obtained experimentally. In the case of alkane oxidation, the composition of the fluidization gas to the reactor was the same as the gas exiting the OCM reactor: 31.16% CH, 0.81% O, 5.58% C olefins, 4.61% C paraffins, 30.09% CO, and 27.78% H. The plastic feed to the reactor consisted of 55.3% polyolefins, 17% polystyrene, 10% PET, and 11% nylon, with the remaining distribution being ABS, PMMA, and biomass. The composition of the catalytic pyrolysis reactor effluent stream for the various configurations is shown in Table 3.

[0072] The differential changes in olefin and aromatic yields for Cases (B) through (D) compared to the base case, single-pass Case (A), are shown in Table 3. As can be seen, adding an alkane oxidation reactor to the recycle loop for the PlasT-Cat conversion reactor results in an overall net increase in olefin and aromatic yield of 6 to 23%. This is further illustrated in Table 4 and Figure 9, which show the product flow rates from various configurations of the PlasT-Cat process at a 500 tpd capacity. As can be seen, Configurations C and D, which include alkane oxidation (OCM), produce higher quality, more valuable products (olefins and aromatics) compared to Configurations A and B. This is also shown in Figure 10, which shows only the total olefin and aromatics products produced from the various PlasT-Cat configurations, and it is clear that Configurations C and D, which include an alkane oxidation reactor, significantly outperform the direct recycle Configuration (B).

[0073] The catalyst circulation rate between the PlasT-Cat reactor and the catalyst generator is determined by the heat balance between the two units. The circulating catalyst must provide sufficient heat to maintain the PlasT-Cat reactor at reaction temperature and also provide the heat necessary for melting and pyrolysis of the feed entering the reactor. The addition of the 840°C alkane oxidation reactor allows for a higher temperature of the fluidization gas entering the PlasT-Cat reactor when compared to the single-pass configuration (A) or the olefin recycle configuration (B), where the fluidization gas enters the reactor at approximately 350°C. In the case of configuration (B), this temperature can be lower, despite excessive coking and thermal runaway in the recycle line. This reduces the heat requirements for the PlasT-Cat reactor and, subsequently, the required catalyst circulation rate. For example, using this condition, the catalyst circulation rate for cases (A) and (B) can be calculated to be 158 kg / s, which is 21% faster than the catalyst circulation rate of 124 kg / s required for cases (C) and (D). The reduced catalyst circulation requirements also reduce the capital cost of the regenerator, improving plant economics. [Table 2] [Table 3] [Table 4] [Table 5]

Claims

1. 1. A method for producing olefins or aromatic compounds, comprising: feeding a plastics-containing stream to a catalytic pyrolysis reactor containing a catalyst; reacting a stream comprising methane or ethane or a hydrocarbon having 1 to 4 carbon atoms with oxygen in an oxidation reactor to produce a product stream comprising ethylene; passing at least a portion of the product stream from the hydrocarbon oxidation in b) to the catalytic pyrolysis reactor; reacting the combined plastics and hydrocarbon oxidation product stream in the catalytic pyrolysis reactor at a temperature greater than 350°C to produce a vapor product; recovering olefins, or aromatics, or some combination thereof, from the vapor product.

2. 10. The process of claim 1, wherein the plastic feed stream comprises waste plastic.

3. The plastic feed stream may be polyethylene (PE), polypropylene (PP), polystyrene (PS), polyester, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyvinyl dichloride (PVDC), acrylonitrile-butadiene-styrene (ABS) copolymer, polyamide, polyurethane, polyether, polycarbonate, poly(oxide), poly(sulfide), polyarylate, polyether ketone, polyetherimide, polysulfone, polyurethane, polyvinyl alcohol, and polymers produced by polymerization of monomers, dienes, olefins, styrene, acrylates, acrylonitrile, 10. The process of claim 1, comprising a plastic selected from methacrylates, methacrylonitrile, diacids and diols, lactones, diacids and diamines, lactams, vinyl esters, or block copolymers thereof, or alloys thereof; thermosetting polymers, epoxy resins; phenolic resins; melamine resins; alkyd resins; vinyl ester resins; unsaturated polyester resins; crosslinked polyurethanes; polyisocyanurates; crosslinked elastomers, including, but not limited to, polyisoprene, polybutadiene, styrene-butadiene, styrene-isoprene, ethylene-propylene-diene monomer polymers, and mixtures thereof.

4. 10. The process of claim 1, wherein the plastic stream comprises a plastic selected from polyethylene terephthalate (PET), high density polyethylene (HDPE), polyvinyl chloride (PVC) or polyvinylidene (PVCD), low density polyethylene (LDPE), polypropylene (PP), polystyrene (PS), or mixed resins, or any combination thereof.

5. 10. The process of claim 1, wherein the plastic feed mixture comprises copolymers such as ethylene-propylene, EPDM, acrylonitrile-butadiene-styrene (ABS), nitrile rubber, natural and synthetic rubber, tires, styrene-butadiene, styrene-acrylonitrile, styrene-isoprene, styrene-maleic anhydride, ethylene-vinyl acetate, nylon 12 / 6 / 66, filled polymers, polymer composites, polymer composites with natural fibers, plastic alloys, other polymeric materials, and polymers or plastics dissolved in a solvent, or combinations thereof.

6. 10. The process of claim 1, wherein the feed material comprises materials obtained from polymer or plastic manufacturing processes, as materials separated from waste streams, such as waste or discarded materials, post-consumer recycled polymeric materials, municipal solid waste (MSW), black liquor, wood waste, or other biologically produced materials, or combinations thereof.

7. 2. The process of claim 1, wherein the feed mixture to the oxidation reactor in b) comprises no more than 5, or 10, or 25, or 50, or 75 volume percent of any one of CO, CO, N, He, or HO, or any combination thereof.

8. 2. The process of claim 1, wherein heat is recovered from the product stream of the hydrocarbon oxidation in b) before a portion thereof is fed to the catalytic pyrolysis reactor.

9. The process of claim 1 wherein the hydrocarbon oxidation is carried out in the presence of a catalyst.

10. 10. The process of claim 1, wherein the oxidation reactor comprises a fixed-bed or fluidized-bed reactor.

11. 2. The process of claim 1, wherein the maximum temperature in the oxidation reactor is at least 500, 600, 700, 800, or 850°C, or up to 1000, 950, 900, or 850°C, or from 500 to 950, 600 to 900, or 700 to 850°C.

12. 2. The process of claim 1, wherein the residence time of the hydrocarbon in the oxidation reactor is no more than 2, 1, 0.5, 0.3, or 0.2 seconds, or from 0.01 to 2, 0.05 to 1, or from 0.2 to 0.5 seconds.

13. 11. The process of claim 10, wherein the weight hourly space velocity of the feed gas is at least 3,000, 5,000, 8,000, 10,000, or 15,000 cm / g-cat-hr, or from 3,000 to 25,000, 5,000 to 15,000, or from 8,000 to 12,000 cm / g-cat-hr.

14. 2. The process of claim 1, wherein the feed to the oxidation reactor has an oxygen atom to carbon atom ratio of 1.2, 1.0, 0.9, 0.8, 0.7, 0.5 or less, or 0.3, or from 0.2 to 1.0, from 0.25 to 0.9, or from 0.3 to 0.

7.

15. 10. The process of claim 1, wherein at least a portion of the feed to the oxidation reactor comprises natural gas or biogas or methane derived therefrom.

16. 10. The process of claim 1, wherein the catalytic pyrolysis reactor is a fluidized bed reactor.

17. 10. The process of claim 1, wherein the non-vapor products of the catalytic pyrolysis, or a portion of the gases remaining after removing the desired products, or both, are combusted to provide energy for the catalytic pyrolysis process.

18. 10. The process of claim 1, wherein at least a portion of the heat generated from the hydrocarbon oxidation in b) is used to heat the pyrolysis reactor, or to heat the fluidization gas to the catalyst regenerator, or as a heat source for other elements of the process.

19. 10. The process of claim 1, wherein the catalytic pyrolysis reaction is carried out in a fluidized bed, circulating bed, bubbling bed, or riser reactor at an operating temperature ranging from 300°C to 800°C, 350°C to 750°C, 400°C to 700°C, 450°C to 650°C, or 500°C to 600°C.

20. 2. The process of claim 1, wherein the absolute pressure in the catalytic pyrolysis reactor is at least 0.1 MPa (1 bara), or at least 0.3 MPa (3 bara), at least 0.4 MPa (4 bara), or from 0.1 to 2.0 MPa (1 to 20 bara), from 0.1 to 1.0 MPa (1 to 10 bara), or from 0.3 to 0.8 MPa (3 to 8 bara), preferably from 0.4 to 0.6 MPa (4 to 6 bara).

21. 10. The process of claim 1, wherein the residence time of the vapor in the catalytic pyrolysis reactor is from 0.5 seconds to 480 seconds, from 0.5 seconds to 240 seconds, from 2 seconds to 60 seconds, from 3 seconds to 30 seconds, or from 4 seconds to 15 seconds.

22. 10. The process of claim 1, wherein the catalyst is a solid catalyst and the step of catalytic pyrolysis comprises pyrolyzing in the presence of the solid catalyst in a fluidized bed reactor to produce a fluid product stream and spent catalyst comprising coke.

23. The process of claim 1 , wherein the catalyst comprises a zeolite.

24. 23. The process of claim 22, wherein the zeolite is at least partially in a protonated form, with at least some of the H+ ions replaced by cations.

25. 10. The process of claim 1, wherein the catalyst may be selected from natural zeolites, synthetic zeolites, and combinations thereof.

26. 2. The process of claim 1, wherein the catalyst may be selected from ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-50, or combinations thereof.

27. The process of claim 1 wherein the catalyst comprises ZSM-5.

28. 10. The process of claim 1, wherein the catalyst composition comprises a crystalline molecular sieve characterized by an SAR of greater than 12 and less than or equal to 240, and a CI of 5-10.

29. 10. The process of claim 1, wherein the catalyst in the fluidized bed comprises a catalytic molecular sieve, and the catalytic molecular sieve comprises 30 to 90 wt. %, or 40 to 70 wt. %, of the composition of the catalyst particles.

30. 10. The process of claim 1, wherein the catalyst in the fluidized bed is in the form of fluidizable particulates.

31. 10. The process of claim 1, wherein the plastic feed mixture is pretreated before being fed to the catalytic pyrolysis reactor.

32. 32. The process of claim 31, wherein the plastic feed mixture is dried to achieve a moisture content of 20, 10, or 5% moisture by weight or less.

33. 32. The process of claim 31, wherein the plastic feed is comminuted to particles having a longest dimension of 40, 20, 10, 5, 2, or 1 mm or less.

34. 32. The process of claim 31, wherein the plastic feed mixture is washed with water, acid, or base, or a sequence of two or more washes with one or more wash solutions.

35. 32. The process of claim 31 , wherein at least a portion of the chlorine-containing plastics is selectively removed from the feed mixture.

36. 32. The process of claim 31, wherein the feed stream of the plastic is first heated to at least 200°C to achieve a molten state and filtered to remove solids.

37. 10. The process of claim 1, wherein the plastic feed mixture is pretreated by pyrolysis in a pyrolysis reactor by anaerobic heating to a temperature of 250-300°C to at least partially decompose the polymers.

38. 38. The process of claim 37, wherein the pretreatment pyrolysis reactor is one or more of a moving bed, single screw extruder, twin screw extruder, Auger reactor, rotary kiln reactor, or staged furnace grate reactor, or some combination thereof.

39. 38. The process of claim 37, wherein the pretreatment pyrolysis reactor comprises an inlet port and an outlet port, the temperature at or near the inlet port being from 20°C to 150°C, for example from 20 to 100°C, or from 20 to 50°C, and the temperature range at the hot outlet port being from 150°C to 300°C, for example from 200 to 275°C, or from 225 to 250°C.

39. 38. The process of claim 37, wherein the pretreatment pyrolysis reactor comprises two or more reactors in series.

40. 38. The process of claim 37, wherein the residence time of the condensed phase in the pretreatment pyrolysis reactor, or in any reactor if more than one reactor is present, is at least 1, 5, 10, 20, or at least 30%, or from 1 to 60, or from 5 to 30, or from 10 to 30 minutes.

41. 38. The process of claim 37, wherein the plastic feed is heated in a pyrolysis reactor to a temperature greater than 150, 175, 200, or 225°C, or from 100 to 350, 150 to 300, 150 to 275, or 150 to 250°C, the vapors are removed, and the condensed phase is passed to the catalytic pyrolysis reactor or to a second pyrolysis reactor.

42. 38. The process of claim 37, wherein the chlorine content in the product of the pretreatment pyrolysis reactor is less than 50, or 20, 10, 5, or 2 ppmw, or from 0.1 to 50, or from 0.5 to 20, or from 1 to 5 ppmw.

43. 38. The process of claim 37, wherein a solid co-reactant material is fed to the pretreatment pyrolysis reactor.

44. 44. The process of claim 43, wherein the solid co-reactant is selected from agricultural lime, calcium oxide, calcium hydroxide, magnesium oxide, magnesium hydroxide, limestone, or hydrotalcite, or some combination thereof.

45. 44. The process of claim 43, wherein said solid co-reactant material is separated from said products of said pretreatment pyrolysis and transferred to a co-reactant regenerator where said carbonaceous material reacts with air and at least a portion of said hot solid co-reactant material is returned to said pyrolysis reactor.

46. 38. The process of claim 37, wherein the product produced in the pretreatment pyrolysis reactor is transferred to the catalytic pyrolysis reactor containing a catalyst without cooling a majority of the product.

47. 2. The process of claim 1, wherein at least a portion of the catalyst is recovered from the catalytic pyrolysis reactor and regenerated by reaction with air or oxygen or an oxidizing gas in a catalyst regenerator, and at least a portion of the regenerated catalyst is returned to the catalytic pyrolysis reactor.

48. 48. The process of claim 47, wherein heat from the catalyst regenerator is provided to the plastic feed or the catalytic pyrolysis reactor.

49. 48. The process of claim 47, wherein a thermal regeneration catalyst provides heat to drive the catalytic pyrolysis process.

50. 10. The process of claim 1, wherein the vapor products of the catalytic pyrolysis are passed through one or more solids separators comprising one or more cyclones.

51. 48. The process of claim 47, wherein at least a portion of the catalyst recovered from the cyclone is fed to the catalyst regenerator.

52. 48. The process of claim 47, wherein a portion of the energy produced in the catalyst regenerator is used as thermal energy within the catalytic pyrolysis reactor or for product separation, or both, or the energy is converted to electrical energy, or the energy produced is used as thermal and electrical energy within the plant or exported, or some combination thereof.

53. 48. The process of claim 47, wherein the net movement of catalyst through the catalyst regenerator is in an upward direction.

54. 48. The process of claim 47, wherein the product vapor mixture of the catalytic pyrolysis is subjected to a separation process to produce a gas stream rich in CH4, CO, and H2, and at least a portion of the gas stream rich in CH4, CO, and H2 is sent to the catalyst regenerator where it is combusted.

55. 10. The process of claim 1, wherein the vapor product of the catalytic pyrolysis is sent to a separation and recovery facility.

56. 10. The process of claim 1, wherein the product vapor mixture from the catalytic pyrolysis comprises at least 20, or at least 30, or at least 50 wt. % olefins, or 20 to 90 wt. % olefins.

57. 10. The process of claim 1, wherein the mass yield of olefins in the product vapor mixture from the catalytic pyrolysis conversion is at least 30%, 40%, 45%, 50%, 55%, or at least 60%, or 20% to 90%, 30% to 70%, or 45% to 60% olefins, based on the mass of the polymer feed.

58. 10. The process of claim 1, wherein the mass yield of BTX in the gaseous product mixture from the catalytic reactor is at least 5%, 10%, 20%, 30%, 35%, or at least 40%, or 1% to 90%, 5% to 70%, 10% to 60%, or 20% to 50% BTX, based on the mass of the polymer feed.

59. 10. The process of claim 1, wherein at least a portion of the recovered olefins is recycled to the catalytic pyrolysis reactor.

60. 10. The process of claim 1, wherein at least a portion of the recovered C1-C4 hydrocarbons is recycled to the oxidation reactor.

61. 10. The process of claim 1, wherein a mixture of benzene, toluene, xylenes, or BTX is recovered from the product vapor mixture.

62. 56. The process of claim 55, wherein the separation and recovery facility processes a feed from a steam cracker or a hydrocracker.

63. 63. The process of claim 62, wherein carbon oxides or water, or both, are at least partially removed from the catalytic pyrolysis product before the product mixture is passed to a separation section of the steam cracker or hydrocracker.

64. 63. The process of claim 62, wherein solids are removed from the product of the catalytic pyrolysis such that the product vapor has a solids content of less than 10 mg / m3, or less than 5 mg / m3, or less than 2 mg / m3, or less than 1 mg / m3 of the product vapor before it is fed to the steam cracker or hydrocracker.

65. 63. The process of claim 62, wherein at least a portion of the methane separated in the steam cracker or hydrocracker separation train is fed to the oxidation reactor.

66. 63. The process of claim 62, wherein methane or ethane or C1-C4 hydrocarbons separated in a separation section of a steam cracker or hydrocracker are fed to the oxidation reactor.

67. 63. The process of claim 62, wherein olefins or aromatics or both are recovered from a separation section of the steam cracker or hydrocracker.

68. 63. The process of claim 62, wherein the chlorine content of the vapor stream fed to the steam cracker or hydrocracker is less than 50, 20, 10, 5, 3, 2, or 1 ppmw, or from 0.1 to 50, 0.5 to 20, or from 1 to 5 ppmw.

69. 10. The process of claim 1, wherein at least a portion of the product mixture from the catalytic pyrolysis is passed to a separation train of a refinery or chemical plant.

70. 1. A reactor for converting plastics to olefins, or aromatics, or a mixture of olefins and aromatics, comprising: a) one or more first conduits for receiving methane or ethane or a mixture of C1-C4 hydrocarbons; b) one or more second conduits for receiving an oxygen-containing gas; d) a first section of the reactor containing a catalyst for oxidation of the stream containing methane or ethane or a mixture of C1-C4 hydrocarbons, wherein oxidation of hydrocarbons occurs in the first section; c) both first and second conduits feed into the first section of the reactor; e) a second section of the reactor downstream of the first section, the second section containing a fluidized bed catalyst for the conversion of a plastics-containing stream to olefins, aromatics, or both, wherein oxidation of hydrocarbons occurs; f) an optional entry port for adding a fluidizing fluid to the reactor downstream of the oxidation catalyst; g) a conduit or device for introducing a plastic-containing feed into said fluidized bed of said catalytic pyrolysis catalyst; h) an outlet port for passing the vapor product mixture of the catalytic pyrolysis through a separation train; i) a port for removing a portion of the fluidized bed catalyst; j) a catalyst regeneration system for reactivating the fluidized bed catalyst; k) an entry port for admitting regenerated catalyst into said fluidized bed.

71. 71. The reactor of claim 70, wherein an adiabatic zone separates the first section of the reactor from the second section of the reactor.

72. 71. The reactor of claim 70, wherein the second section of the reactor is above the first section of the reactor and the entire flow of gas through the reactor is in an upward direction relative to gravity.

73. 72. The reactor of claim 71, wherein the insulating zone is fitted with insulating material that absorbs or reflects heat radiation.

74. 71. The reactor of claim 70, wherein a fluidizing fluid is introduced into the reactor in the adiabatic or mixing zone after the first section of the reactor and before the second section of the reactor.

75. 75. The reactor of claim 74, wherein the temperature of the fluidizing fluid entering the reactor is less than the temperature of the product gas exiting the first section of the reactor.

76. 71. The reactor of claim 70, wherein the fluidizing fluid and the product stream of hydrocarbon oxidation product gas are mixed in the adiabatic zone.

77. 77. The reactor of claim 76, wherein the temperature of the gas mixture of the hydrocarbon oxidation product gas and fluidizing fluid is less than 900, 850, 800, 750, 700, or 650°C.

78. 71. The reactor of claim 70, wherein the relative volumetric flow rates of the fluidizing fluid and the hydrocarbon oxidation product gas stream can be in the range of 0.1:1 to 10:1, 0.5:1 to 5:1, or 1:1 to 3:1, or can be greater than 0.1:1, 0.3:1, or 1:

1.

79. 75. The reactor of claim 74, wherein the fluidizing fluid temperature upon entering the mixing zone can be less than 650, 550, 500, 450, 400, 300, or 200°C, or a temperature in the range of 100 to 650, 100 to 500, or 100 to 400°C.

80. 72. The reactor of claim 71, wherein the adiabatic zone is fitted with distribution plate(s), baffles, beryl saddles, or other shaped objects, or some combination thereof.

81. 72. The reactor of claim 71, wherein the fluidizing fluid is introduced into the mixing zone through one or more introduction ports which can be positioned tangentially, radially, or at an intermediate angle relative to the axis of the reactor.

82. 71. The reactor of claim 70, wherein the reactor is fitted with one or more distributor plates in the adiabatic or mixing zone that distribute the oxidation product stream and any added fluidizing fluid to the catalytic pyrolysis zone through one or more ports.

83. 83. The reactor of claim 82, wherein the ports in the distributor plate(s) can be sized and shaped to ensure a superficial flow velocity of the gas mixture at the outlet of the port is greater than 1.0, 1.5, 2.0, 3.0, or 5.0 meters / second.

84. 71. The reactor of claim 70, wherein the first section of the reactor comprises one or more lift pipes that mix the fluidization fluid and oxidation product stream before entering the catalytic pyrolysis portion of the reactor.

85. 85. The reactor of claim 82, 83, or 84, wherein the ports in the one or more distributor plates or the one or more lift pipes are each terminated with a cap that directs flow out of the port or pipe downward.

86. 86. The reactor of claim 84 or 85, wherein the cross-sectional area of ​​any lift pipe is less than 30%, 30%, 25%, 20%, 15%, 10%, 5%, or 3%, or between 1% and 20%, or between 2% and 15%, or between 3% and 10% of the cross-sectional area of ​​the fluidized bed catalytic reaction zone.

87. 71. The reactor of claim 70, wherein a catalyst drain is attached at or near the bottom of the fluidized catalyst bed to facilitate removal of a portion of the catalyst in a continuous manner.

88. 71. The reactor of claim 70, wherein the reactor forms part of a reaction system that also includes a pretreatment pyrolysis reactor, or a catalyst regenerator, or both.

89. 71. The reactor of claim 70, wherein an outlet conduit from the catalytic pyrolysis reactor supplies the product gas to one or more cyclones in which solids are separated, at least a portion of the solids are returned to the fluidized bed, and a remaining portion of the separated solids are discarded.

90. 10. The process of claim 1, wherein the oxidation reaction is carried out in an anaerobic reactor separate from the catalytic pyrolysis reactor.

91. 10. The process of claim 1, wherein the oxidation reaction is carried out in a non-anaerobic reactor separate from the catalytic pyrolysis reactor, and heat from the oxidation reaction is transferred to the plastic pretreatment, catalytic pyrolysis, fluidization fluid, or used in a separation process, or some combination thereof.

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