Catalytic pyrolysis of plastics to produce petrochemical feedstocks

Abstract

The present technology generally relates to a process for converting plastics to olefins and aromatics by pyrolysis, the process producing at least one or more of olefins and aromatics from a plastic feedstock comprising contacting the plastic feedstock with a catalyst composition in a conical spouted bed reactor at a temperature of from about 450° C. to about 650° C. for a period of time sufficient to convert at least a portion of the plastic feedstock to at least one or more olefins and aromatics, the catalyst composition comprising greater than about 40% w / w ZSM-5, based on the total weight of the catalyst composition.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 252,861, filed October 6, 2021, which is hereby incorporated by reference in its entirety for all purposes.

[0002] FIELD OF THEINVENTION The present technology relates generally to the conversion of plastics to olefins and aromatics by pyrolysis. Specifically, the present technology relates to catalyst compositions comprising greater than 40% w / w ZSM-5 and methods of preparing and using such compositions in a conical spouted bed reactor for the catalytic pyrolysis of plastics to olefins and aromatics. [Background technology]

[0003] Catalytic pyrolysis, which involves the decomposition of polymeric materials by heating them in the absence of oxygen and in the presence of a catalyst, is an attractive method for recycling plastic waste. Silica-alumina, zeolites, and fluid catalytic cracking (FCC) catalysts are commonly used to lower energy requirements, influence product composition throughout the cracking, and shorten process times. Although catalytic pyrolysis has been widely studied, there remains a need to develop more efficient catalytic pyrolysis methods that maximize the yield of desirable products such as light olefins and aromatics, and minimize the yield of undesirable products such as methane and ethane. Propylene, in particular, is a particular light olefin in high demand because of its use in many of the world's largest and fastest growing synthetic and thermoplastic materials.

[0004] The present disclosure provides a process for catalytic pyrolysis of waste plastics using a spouted bed reactor comprising a draft tube and a confiner having a catalyst composition comprising greater than 40% w / w ZSM-5 to provide high yields of petrochemical feedstocks such as ethylene, propylene, butylene. Summary of the Invention

[0005] One embodiment is a process for producing at least one or more of olefins and aromatic compounds from a plastic feedstock, the process comprising contacting the plastic feedstock with a catalyst composition in a conical spouted bed reactor at a temperature of from about 450° C. to about 650° C. and for a period of time sufficient to convert at least a portion of the plastic feedstock to at least one or more olefins and aromatic compounds, the catalyst composition comprising greater than about 40% w / w ZSM-5, based on the total weight of the catalyst composition.

[0006] In some embodiments, the catalyst composition comprises greater than about 45% w / w, about 55% w / w, about 60% w / w, about 65% w / w, about 70% w / w, about 75% w / w, or about 80% w / w ZSM-5 based on the total weight of the catalyst composition.

[0007] In some embodiments, the catalyst composition comprises from about 40% w / w to about 80% w / w, from about 45% w / w to about 80% w / w, from about 50% w / w to about 80% w / w, from about 55% w / w to about 80% w / w, from about 60% w / w to 80% w / w, from about 65% w / w to about 80% w / w, from about 70% w / w to about 80 w / w, or from about 75% w / w to about 80% w / w of ZSM-5, based on the total weight of the catalyst composition.

[0008] In some embodiments, the catalyst composition comprises particles having a size ranging from about 0.05 mm to about 5 mm. In some embodiments, the catalyst composition comprises particles having a size ranging from about 0.8 mm to about 5 mm or from about 1.0 mm to about 2.5 mm.

[0009] In some embodiments, the catalyst composition comprises particles having a size of about 0.05, about 0.06 mm, about 0.07 mm, about 0.08 mm, about 0.09 mm, about 0.1 mm, about 0.2 mm, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, about 1.0, about 1.1, about 1.2, about 1.3, about 1.4, about 1.5, about 1.6, about 1.7, about 1.8, about 1.9, about 2.0, about 2.1, about 2.2, about 2.3, about 2.4, or about 2.5 mm.

[0010] In some embodiments, the catalyst composition comprises about 5% w / w to about 15% w / w P2O5 based on the total weight of the composition. In some embodiments, the catalyst composition comprises about 5%, about 6%, about 7%, about 8%, about 9%, about 10%, about 11%, about 12%, about 13%, about 14%, or about 15% w / w P2O5 based on the total weight of the composition.

[0011] In some embodiments, the catalyst composition comprises up to about 40% w / w Al2O3, based on the total weight of the composition.

[0012] In some embodiments, the ZSM-5 has a crystallite size of less than about 0.4 microns.

[0013] In some embodiments, the catalyst composition is formed by spray drying, extrusion, or a bead-forming method. In some embodiments, the bead-forming method is agglomeration.

[0014] In some embodiments, the ZSM-5 is combined with the active matrix within a particle, hi some embodiments, the ZSM-5 is combined with the active matrix as a separate particle.

[0015] In some embodiments, ZSM-5 is combined with one or more zeolites selected from ZSM-11, faujasite, mordenite, and beta. In some embodiments, the combination of ZSM-5 with one or more zeolites promotes the thermal cracking of polymers.

[0016] In some embodiments, ZSM-5 is combined as separate particles with one or more Y-type zeolites selected from zeolite Y, ultrastable Y zeolite (USY), rare earth exchanged Y (REY), rare earth exchanged USY (REUSY), dealuminated Y (DeAIY), and ultrahydrophobic Y (UHPY).

[0017] In some embodiments, contacting the plastic feedstock with the catalyst composition is at a temperature of about 500° C. to about 600° C. In some embodiments, contacting the plastic feedstock with the catalyst composition is at a temperature of about 450° C., about 460° C., about 470° C., about 480° C., about 490° C., about 500° C., about 510° C., about 520° C., about 530° C., about 540° C., about 550° C., about 560° C., about 570° C., about 580° C., about 590° C., about 600° C., about 610° C., about 620° C., about 630° C., about 640° C., or about 650° C.

[0018] In some embodiments, the plastic feedstock comprises at least one of polyolefins, polyethylene, polypropylene, polystyrene, polyethylene terephthalate (PET), polyvinylchloride (PVC), polyamides, polycarbonates, polyurethanes, polyesters, natural and synthetic rubbers, tires, filled polymers, composites, plastic alloys, and plastics dissolved in a solvent. In some embodiments, the plastic feedstock comprises polyethylene (e.g., high-density polyethylene (HDPE)) dissolved in a solvent. In some embodiments, the plastic feedstock comprises polypropylene dissolved in a solvent.

[0019] In some embodiments, the at least one olefin is selected from ethylene, propylene, and butene. In some embodiments, the process converts the plastic feedstock to greater than about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, or about 70% ethylene, propylene, and butene by weight. In some embodiments, the process converts the plastic feedstock to greater than about 20%, about 25%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, or about 70% propylene by weight.

[0020] In some embodiments, the at least one aromatic compound is selected from benzene, toluene, and xylene.

[0021] In some embodiments, the period of time sufficient to convert at least a portion of the plastic feedstock to at least one or more olefins and aromatics is a space time ranging from about 0.2 to about 10 hours.

[0022] In some embodiments, the conical spouted bed reactor comprises a draft tube and a restrictor. As shown in FIG. O gas inlet opening, and D C The diameter of the cylindrical part of the conical spouted bed reactor is D G The draft tube has a diameter of H G In some embodiments, the distance from the top of the draft tube to the bottom of the draft tube is H G Approx. 3 to 4 x D O In some embodiments, H G Approximately 1.5 to 2.5 x D O In some embodiments, H G is about 2 x D O In some embodiments, D G Approximately 3 x D O ~about 0.7D CIn some embodiments, D G Approx. 4 to 6 x D O In some embodiments, D G is about 5×D O It is. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a schematic diagram of a conventional spouted bed reactor from the prior art. [Diagram 2] FIG. 1 is a schematic diagram of a spouted bed reactor having a draft tube and a restrictor according to an illustrative embodiment. [Diagram 3] 1A-1C are schematic diagrams of two exemplary embodiments of a draft tube having an open sidewall and a closed sidewall. [Figure 4] FIG. 1 is a schematic diagram of a draft tube and restrictor arrangement with illustrated dimensions. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Various embodiments are described below. It should be noted that the specific embodiments are not intended as an exhaustive description or as a limitation to the broader aspects discussed herein. An aspect described in conjunction with a specific embodiment is not necessarily limited to that embodiment and can be practiced in any other embodiment.

[0025] As used herein, "about" will be understood by one of ordinary skill in the art and will vary to some extent depending on the context in which it is used. If there are uses of the term that are not clear to persons of ordinary skill in the art, given the context in which it is used, "about" will mean up to plus or minus 10% of the particular term.

[0026] "A" and "an" and "the" and similar referents in the context of describing elements (particularly in the context of the claims below) should be construed to cover both the singular and the plural, unless otherwise indicated herein or the content clearly contradicts. The recitation of ranges of values ​​herein is merely intended to serve as a shorthand method of referring individually to each separate value within the range, unless otherwise indicated herein, and each separate value is incorporated herein as if it were individually recited herein. All methods described herein may be performed in any suitable order, unless otherwise indicated herein or the content clearly contradicts otherwise. The use of any and all examples or exemplary language (e.g., "etc.") provided herein is intended merely to better illustrate the embodiments and does not impose limitations on the scope of the claims, unless otherwise specified. No language in this specification should be construed as indicating any non-claimed element as essential.

[0027] Disclosed herein is a process for the high yield conversion of waste plastics into valuable petrochemical feedstocks such as propylene using a spouted bed reactor comprising a draft tube and a restrictor and a catalyst composition comprising greater than about 40% w / w ZSM-5 based on the total weight of the catalyst composition.

[0028] As shown in the examples, the inventors of the present disclosure have discovered that by using a spouted bed reactor including a draft tube and restrictor in combination with a catalyst including greater than 40% w / w ZSM-5, plastics can be catalytically converted in high yields into petrochemical feedstocks such as ethylene, propylene, butylene, etc. These petrochemical feedstocks can be reprocessed into useful plastics for a more circular economy.

[0029] ZSM-5 catalyst composition The catalyst composition described herein comprises greater than 40% w / w ZSM-5 (U.S. Pat. No. 3,702,886 and RE29,948), a shape selective zeolite, based on the total weight of the catalyst composition. In some embodiments, the catalyst composition comprises greater than about 45% w / w, about 55% w / w, about 60% w / w, about 65% w / w, about 70% w / w, about 75% w / w, or about 80% w / w ZSM-5, based on the total weight of the catalyst composition.

[0030] In some embodiments, the catalyst composition comprises about 40% w / w to about 80% w / w, about 45% w / w to about 80% w / w, about 50% w / w to about 80% w / w, about 55% w / w to about 80% w / w, about 60% w / w to 80% w / w, about 65% w / w to about 80% w / w, about 70% w / w to about 80 w / w, or about 75% w / w to about 80% w / w of ZSM-5 based on the total weight of the catalyst composition. In some embodiments, the catalyst composition comprises about 40% w / w, about 45% w / w, about 55% w / w, about 60% w / w, about 65% w / w, about 70% w / w, about 75% w / w, or about 80% w / w of ZSM-5 based on the total weight of the catalyst composition.

[0031] The catalyst compositions described herein may include particles having a size ranging from about 0.05 mm to about 5 mm. In some embodiments, the catalyst compositions include particles having a size ranging from about 0.8 mm to about 5 mm or from about 1.0 mm to about 2.5 mm. In some embodiments, the catalyst composition comprises particles having a size of about 0.05, about 0.06 mm, about 0.07 mm, about 0.08 mm, about 0.09 mm, about 0.1 mm, about 0.2 mm, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, about 1.0, about 1.1, about 1.2, about 1.3, about 1.4, about 1.5, about 1.6, about 1.7, about 1.8, about 1.9, about 2.0, about 2.1, about 2.2, about 2.3, about 2.4, about 2.5 mm, about 3.0 mm, about 3.5 mm, about 4.0 mm, about 4.5 mm, or about 5.0 mm.

[0032] The catalyst compositions described herein may comprise about 5% w / w to about 15% w / w P2O5 based on the total weight of the composition. In some embodiments, the catalyst compositions comprise about 5%, about 6%, about 7%, about 8%, about 9%, about 10%, about 11%, about 12%, about 13%, about 14%, or about 15% w / w P2O5 based on the total weight of the composition.

[0033] The catalyst compositions described herein may comprise about 40% w / w or less Al2O3, including about 35% w / w or less, about 30% w / w or less, about 25% w / w or less, and about 20% w / w or less, based on the total weight of the composition. In some embodiments, the catalyst compositions comprise about 40% w / w, about 35% w / w, about 30% w / w, about 25% w / w, about 20% w / w Al2O3, based on the total weight of the composition.

[0034] In some embodiments, the ZSM-5 has a crystallite size of less than about 0.4 microns, including less than about 0.3, less than about 0.2, less than about 0.1, less than about 0.09, less than about 0.08, less than about 0.07, less than about 0.06, less than about 0.05, less than about 0.04, less than about 0.03, less than about 0.02, and less than about 0.01 microns. In some embodiments, the ZSM-5 has a crystallite size of from about 0.01 microns to about 0.4 microns, including about 0.01, about 0.02, about 0.03, about 0.04, about 0.05, about 0.06, about 0.07, about 0.08, about 0.09, about 0.1, about 0.2, about 0.3, or about 0.4 microns.

[0035] The catalyst compositions described herein may be formed by bead-forming methods such as spray drying, extrusion, or agglomeration. In some embodiments, the catalyst compositions are formed by spray drying. In some embodiments, the catalyst compositions are formed by extrusion. In some embodiments, the catalyst compositions are formed by bead-forming methods including agglomeration.

[0036] In some embodiments, the ZSM-5 is combined with the active matrix within a particle, hi some embodiments, the ZSM-5 is combined with the active matrix as a separate particle.

[0037] In some embodiments, ZSM-5 is combined with one or more zeolites selected from ZSM-11, faujasite, mordenite, and beta. In some embodiments, the combination of ZSM-5 with one or more zeolites promotes the thermal cracking of polymers.

[0038] In some embodiments, ZSM-5 is combined as separate particles with one or more Y-type zeolites selected from zeolite Y (U.S. Pat. No. 3,130,007), ultrastable Y zeolite (USY) (U.S. Pat. No. 3,449,070), rare earth exchanged Y (REY) (U.S. Pat. No. 4,415,438), rare earth exchanged USY (REUSY), dealuminated Y (DeAIY) (U.S. Pat. Nos. 3,442,792 and 4,331,694), and superhydrophobic Y (UHPY) (U.S. Pat. No. 4,401,556).

[0039] Conical Spouted Bed Reactor The use of spouted bed reactors to carry out plastic pyrolysis reactions has been disclosed; however, the spouted bed reactors disclosed prior to this disclosure did not have a draft tube or restrictor. Furthermore, the catalysts used in these spouted bed reactors were extrudates containing approximately 20-25% fresh ZSM-5 and were not deactivated to simulate commercial performance.

[0040] FIG. 1 shows a schematic diagram of a conventional conical spouted bed reactor disclosed in the prior art, which does not have a draft tube or restrictor. An inert gas, such as nitrogen or water vapor, is introduced into the catalyst bed through an orifice at the base of the reactor. The flowing gas forms a cylindrical channel or spout through the catalyst bed. The catalyst entrained by the gas flowing through the spout is propelled above the surface of the catalyst bed and settles back down in the shape of a fountain. The catalyst travels down the annular region and returns to the bottom of the conical bed, thus completing the cycle. The rapid circulation of catalyst and reactants ensures good mixing in the reactor. The spout region is a region of low catalyst density, called the dilute phase, and the annular region is a region of high catalyst density, called the dense phase. In the absence of a draft tube, some of the gas would flow around the spout and through the annular region.

[0041] In contrast, the catalytic pyrolysis process of plastic waste described herein uses a conical spouted bed reactor that includes a draft tube and a restrictor. Figure 2 shows a schematic of an exemplary embodiment. Figure 3 shows two examples of draft tubes with open and closed sidewalls. Gas flowing through the draft tube creates a region of negative pressure at the bottom of the tube, which draws in catalyst from the annular region and propels it up the draft tube. The restrictor, which is closed at the top, redirects the catalyst downward.

[0042] The draft tube directs the gas through the jets so that less gas travels through the annulus compared to a conventional spouted bed reactor, and therefore the minimum jet velocity with the draft tube is much lower than without it.

[0043] The restrictor restricts the dilute phase to a smaller volume with more turbulent mixing. The feedstock added to the restrictor is rapidly mixed with the catalyst. The higher collision frequency between the catalyst and plastic results in faster heat transfer, melting of the plastic, and distribution of the molten plastic throughout the catalyst.

[0044] FIG. 4 shows an exemplary embodiment of the draft tube and restrictor arrangement with major dimensions. The conical spouted bed reactor is O gas inlet opening, and D C The diameter of the cylindrical part of the conical spouted bed reactor is D G The draft tube has a diameter of H G The distance from the top of the draft tube to the bottom of the draft tube is .

[0045] In some embodiments, H G Approx. 3 to 4 x D O Or about 1.5~2.5×D O In some embodiments, H G is about 2 x D O It is.

[0046] In some embodiments, D G Approximately 3 x D O ~about 0.7D C Or about 4 to about 6 x D O In some embodiments, D G is about 5×D O It is.

[0047] Catalytic pyrolysis Disclosed herein is a process for producing at least one or more of olefins and aromatic compounds from a plastic feedstock, the process comprising contacting the plastic feedstock with a catalyst composition in a conical spouted bed reactor at a temperature of about 450° C. to about 650° C. and for a period of time sufficient to convert at least a portion of the plastic feedstock to at least one or more olefins and aromatic compounds, the catalyst composition comprising greater than about 40% w / w ZSM-5, based on the total weight of the catalyst composition.

[0048] In some embodiments, contacting the plastic feedstock with the catalyst composition is at a temperature of about 500°C to about 600°C, including about 525°C to about 575°C. In some embodiments, contacting the plastic feedstock with the catalyst composition is at a temperature of about 450°C, about 460°C, about 470°C, about 480°C, about 490°C, about 500°C, about 510°C, about 520°C, about 530°C, about 540°C, about 550°C, about 560°C, about 570°C, about 580°C, about 590°C, about 600°C, about 610°C, about 620°C, about 630°C, about 640°C, or about 650°C. In some embodiments, contacting the plastic feedstock with the catalyst composition is at a temperature of about 550°C.

[0049] The plastic feedstock described herein may include at least one of polyolefins, polyethylene, polypropylene, polystyrene, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyamides, polycarbonates, polyurethanes, polyesters, natural and synthetic rubbers, tires, filled polymers, composites, plastic alloys, and plastics dissolved in a solvent. In some embodiments, the plastic feedstock includes polyethylene (e.g., high density polyethylene (HDPE)) dissolved in a solvent. In some embodiments, the plastic feedstock includes polypropylene dissolved in a solvent.

[0050] For the catalytic processes described herein, the reaction product may include at least one or more olefins selected from ethylene, propylene, and butenes (e.g., light olefins). In some embodiments, the process converts the plastic feedstock to greater than about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, or about 70% ethylene, propylene, and butenes by weight. In some embodiments, the process converts the plastic feedstock to about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, or about 70% ethylene, propylene, and butenes by weight.

[0051] In some embodiments, the catalytic process described herein provides a high yield of propylene. In some embodiments, the process converts the plastic feedstock to more than about 20% by weight, about 25% by weight, about 35% by weight, about 40% by weight, about 45% by weight, about 50% by weight, about 55% by weight, about 60% by weight, about 65% by weight, or about 70% by weight of propylene. In some embodiments, the process converts the plastic feedstock to about 20% by weight, about 25% by weight, about 35% by weight, about 40% by weight, about 45% by weight, about 50% by weight, about 55% by weight, about 60% by weight, about 65% by weight, or about 70% by weight of propylene.

[0052] The reaction products for the catalytic process described herein may include at least one or more aromatic compounds selected from benzene, toluene, and xylene. In some embodiments, the process converts the plastic feedstock to more than about 20% by weight, about 25% by weight, about 35% by weight, about 40% by weight, about 45% by weight, about 50% by weight, about 55% by weight, about 60% by weight, about 65% by weight, or about 70% by weight of one or more aromatic compounds. In some embodiments, the process converts the plastic feedstock to about 20% by weight, about 25% by weight, about 35% by weight, about 40% by weight, about 45% by weight, about 50% by weight, about 55% by weight, about 60% by weight, about 65% by weight, or about 70% by weight of one or more aromatic compounds.

[0053] The period of time sufficient to convert at least a portion of the plastic feedstock to at least one or more olefins and aromatics is a space time ranging from about 0.2 to about 10 hours, including about 0.2, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, about 1, about 1.5, about 2, about 2.5, about 3, about 3.5, about 4, about 4.5, about 5, about 5.5, about 6, about 6.5, about 7, about 7.5, about 8, about 8.5, about 9, about 9.5, or about 10 hours. As used herein, space time refers to 1 / WHSV (weight hourly space velocity) or "weight of catalyst in reactor" / "hourly feed rate".

[0054] In some embodiments, the period of time sufficient to convert at least a portion of the plastic feedstock to at least one or more olefins and aromatics is a gas phase residence time (about 0.5 to about 5 seconds) and / or a catalyst residence time (about 2 to about 10 minutes). In some embodiments, the gas phase residence time is about 0.5 to about 5 seconds, including about 0.5, about 1, about 1.5, about 2, about 2.5, about 3, about 3.5, about 4, about 4.5, and about 5 seconds. In some embodiments, the catalyst residence time is about 2 to about 10 minutes, including about 2, about 2.5, about 3, about 3.5, about 4, about 4.5, about 5, about 5.5, about 6, about 6.5, about 7, about 7.5, about 8, about 8.5, about 9, about 9.5, or about 10 minutes.

[0055] The invention having thus been generally described will be more readily understood with reference to the following examples, which are provided by way of illustration and are not intended to limit the invention. EXAMPLES

[0056] Example 1 The use of spouted bed reactors to carry out plastic pyrolysis reactions has been disclosed; however, the spouted bed reactors disclosed prior to this disclosure did not have a draft tube or restrictor. Furthermore, the catalysts used in these spouted bed reactors were extrudates containing approximately 20-25% fresh ZSM-5 and were not deactivated to simulate commercial performance.

[0057] A schematic diagram of a conventional conical spouted bed reactor without a draft tube or restrictor is shown in Figure 1 and used in the following examples. An inert gas, such as nitrogen or water vapor, is introduced into the catalyst bed through an orifice at the base of the reactor. The flowing gas forms a cylindrical path or spout through the catalyst bed. The catalyst entrained by the gas flowing through the spout is propelled above the surface of the catalyst bed and settles back down in the shape of a fountain. The catalyst travels down the annular region and returns to the bottom of the conical bed, thus completing the cycle. The rapid circulation of catalyst and reactants ensures good mixing in the reactor. The spout region is a region of low catalyst density called the dilute phase, and the annular region is a region of high catalyst density called the dense phase. In the absence of a draft tube, some of the gas would flow around the spout and through the annular region.

[0058] Example 2 Figure 2 shows a schematic of a spouted bed reactor with a draft tube and restrictor (top) used in the examples below. Two examples of draft tubes with open and closed sidewalls are shown in Figure 3. Gas flowing through the draft tube creates a region of negative pressure at the bottom of the tube, which draws catalyst from the annular region and propels it up the draft tube. The restrictor, which is closed at the top, redirects the catalyst downward.

[0059] The draft tube directs the gas through the jets so that less gas travels through the annulus compared to a conventional spouted bed reactor, and therefore the minimum jet velocity with the draft tube is much lower than without it.

[0060] The restrictor restricts the dilute phase to a smaller volume with more turbulent mixing. The feedstock added to the restrictor is rapidly mixed with the catalyst. The higher collision frequency between the catalyst and plastic results in faster heat transfer, melting of the plastic, and distribution of the molten plastic throughout the catalyst.

[0061] The major dimensions of the draft tube and restrictor arrangement are shown in FIG. 4. DO refers to the gas inlet opening of the spouted bed. DC refers to the diameter of the cylindrical part of the spouted bed, and DG refers to the diameter of the restrictor. HG refers to the distance from the top of the draft tube to the bottom of the restrictor. HG can be about 3-4×DO. In some embodiments, HG can be about 1.5-2.5×DO. In some embodiments, HG should be about 2×DO. In some embodiments, DG can be about 3×DO to 0.7×DC. In some embodiments, DG can be about 4-6×DO, or about 5×DO.

[0062] Example 3 Agglomerated catalyst samples with an average particle size of 2 mm were prepared as described below. Dry powders of ZSM-5, pseudoboehmite alumina and halloysite clay were thoroughly mixed in an Eirich mixer. Water or a solution of phosphoric acid and water was sprayed onto the powders while stirring. The resulting agglomerates were dried, calcined and steamed at 1500°F for 24 hours to simulate catalyst deactivation during commercial application. A catalyst showing an exemplary embodiment containing 40% ZSM-5 (Catalyst A) and a comparative sample containing 30% ZSM-5 but with a higher pseudoboehmite content (Catalyst B) were prepared. The catalyst properties are shown in Table 1.

[0063] [Table 1]

[0064] Example 4 135 grams of catalyst A from Example 3 was loaded into a conventional spouted bed reactor and heated to 550° C. with 30 NL / min of nitrogen used as the blowing gas. HDPE was loaded into the reactor at 1 g / min. The reaction products are shown in Table 2. 135 grams of catalyst A from Example 3 was added to the same reactor as above, except that a draft tube and restrictor were installed in the reactor. The addition of the draft tube and restrictor reduced the minimum blowing velocity, defined as the velocity of the nitrogen at the inlet of the reactor when the catalyst bed begins to blow. With the inclusion of the draft tube and restrictor, a stable spouted bed was established with a nitrogen flow of 10 NL / min compared to 30 NL / min without the use of a draft tube or restrictor. The reaction products from this experiment are also shown in Table 2.

[0065] The use of a draft tube and restrictor significantly increased the yields of propylene and butenes and reduced the formation of heavy oil in the >C12 range. A combined light olefin yield (ethylene, propylene, and butenes) of greater than 50 wt% was achieved by combining a conical spouted bed reactor with a draft tube and restrictor and a catalyst composition with greater than 40% w / w ZSM-5.

[0066] [Table 2]

[0067] Example 5 Catalysts A (exemplary embodiment) and B (comparative example) from Example 3, containing 40% and 30% ZSM-5, respectively, were used for the catalytic pyrolysis of polypropylene in a spouted bed reactor containing a draft tube and restrictor. Polypropylene (160° C. mp) is more difficult to convert to lighter products than HDPE (135° C. mp) due to its higher melting point. However, the data in Table 3 show that catalyst A, containing 40% ZSM-5, is able to convert PP to 48.6 wt.% total light olefins (ethylene, propylene, and butenes), which is almost the same as for HDPE. However, with only 30% ZSM-5 content, catalyst B produced about 0.2% less ethylene, 3.9% less propylene, and 1.8% less butenes. These results show that the combination of a conical spouted bed reactor with a draft tube and restrictor and a catalyst composition with more than 40% w / w ZSM-5 produced high yields of light olefins from plastic pyrolysis suitable for petrochemical feedstocks.

[0068] [Table 3]

[0069] Example 6 Spray-dried catalyst samples with an average particle size of 70 microns were prepared as described below. A 40% slurry of zeolite, pseudoboehmite alumina, phosphoric acid, and halloysite clay was sent to spray drying and then calcined at 450-600°C to produce spherical particles with 0.2-2 wt% TV. The resulting particles were steamed at 1500°F for 24 hours to simulate catalyst deactivation during commercial application. Exemplary embodiment catalysts containing 40% and 55% ZSM-5, respectively (Catalysts C and D) were compared with the same catalysts blended with 50% commercial faujasite-based FCC catalyst (Comparative Samples, Catalysts E and F). The catalyst properties are shown in Table 4.

[0070] [Table 4]

[0071] Example 7 Catalysts C and D (exemplary embodiments) and Catalysts E and F (comparative examples) from Example 6 were used for catalytic pyrolysis of polyethylene in a spouted bed reactor containing a draft tube and restrictor. The results are summarized in Table 5. The results show that the addition of the Y zeolite-zeolite based catalyst as a 50 / 50 blend with the ZSM-5 catalyst reduces the olefin yield (compare Catalyst C with Catalyst E and Catalyst D with Catalyst F).

[0072] [Table 5]

[0073] Paragraph 1. A process for producing at least one of olefins and aromatic compounds from a plastic feedstock, the process comprising: contacting a plastic feedstock with a catalyst composition in a conical spouted bed reactor at a temperature of about 450° C. to about 650° C. for a period of time sufficient to convert at least a portion of the plastic feedstock to at least one or more olefins and aromatic compounds; The process wherein the catalyst composition comprises greater than about 40% w / w ZSM-5, based on the total weight of the catalyst composition.

[0074] Paragraph 2. The process of Paragraph 1, wherein the catalyst composition comprises greater than about 45% w / w, about 55% w / w, about 60% w / w, about 65% w / w, about 70% w / w, about 75% w / w, or about 80% w / w ZSM-5, based on the total weight of the catalyst composition.

[0075] Paragraph 3. The process of Paragraph 1, wherein the catalyst composition comprises from about 40% w / w to about 80% w / w, from about 45% w / w to about 80% w / w, from about 50% w / w to about 80% w / w, from about 55% w / w to about 80% w / w, from about 60% w / w to 80% w / w, from about 65% w / w to about 80% w / w, from about 70% w / w to about 80 w / w, or from about 75% w / w to about 80% w / w of ZSM-5, based on the total weight of the catalyst composition.

[0076] Paragraph 4. The process of any one of Paragraphs 1-3, wherein the catalyst composition comprises particles having a size ranging from about 0.05 mm to about 5 mm.

[0077] Paragraph 5. The process of any one of Paragraphs 1 to 4, wherein the catalyst composition comprises particles having a size of about 0.8 mm to about 5 mm or about 1.0 mm to about 2.5 mm.

[0078] Paragraph 6. The process of any one of Paragraphs 1-5, wherein the catalyst composition comprises particles having a size of about 0.05, about 0.06 mm, about 0.07 mm, about 0.08 mm, about 0.09 mm, about 0.1 mm, about 0.2 mm, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, about 1.0, about 1.1, about 1.2, about 1.3, about 1.4, about 1.5, about 1.6, about 1.7, about 1.8, about 1.9, about 2.0, about 2.1, about 2.2, about 2.3, about 2.4, or about 2.5 mm.

[0079] Paragraph 7. The process of any one of Paragraphs 1 to 6, wherein the catalyst composition comprises about 5% w / w to about 15% w / w of P2O5, based on the total weight of the composition.

[0080] Paragraph 8. The process of any one of Paragraphs 1-7, wherein the catalyst composition comprises about 5%, about 6% w / w, about 7% w / w, about 8% w / w, about 9% w / w, about 10% w / w, about 11% w / w, about 12% w / w, about 13% w / w, about 14% w / w, or about 15% w / w of P2O5, based on the total weight of the composition.

[0081] Paragraph 9. The process of any one of Paragraphs 1 to 8, wherein the catalyst composition comprises about 40% w / w or less Al2O3, based on the total weight of the composition.

[0082] Paragraph 10. The process of any one of Paragraphs 1 to 9, wherein the ZSM-5 has a crystallite size of less than about 0.4 microns.

[0083] Paragraph 11. The process of any one of Paragraphs 1 to 10, wherein the catalyst composition is formed by spray drying, extrusion, or a bead formation method.

[0084] Paragraph 12. The process of paragraph 11, wherein the bead formation method is agglomeration.

[0085] Paragraph 13. The process of any one of paragraphs 1 to 12, wherein the ZSM-5 is combined with an active matrix within a particle.

[0086] Paragraph 14. The process of any one of paragraphs 1 to 12, wherein the ZSM-5 is combined with the active matrix as separate particles.

[0087] Paragraph 15. The process of any one of Paragraphs 1 to 14, wherein ZSM-5 is combined with one or more zeolites selected from ZSM-11, faujasite, mordenite, and beta.

[0088] Paragraph 16. The process of Paragraph 15, wherein the combination of ZSM-5 and one or more zeolites promotes the thermal cracking of polymers.

[0089] Paragraph 17. The process of Paragraph 16, wherein ZSM-5 is combined as separate particles with one or more Y-type zeolites selected from zeolite Y, ultrastable Y zeolite (USY), rare earth exchanged Y (REY), rare earth exchanged USY (REUSY), dealuminated Y (DeAIY), and superhydrophobic Y (UHPY).

[0090] Paragraph 18. The process of any one of Paragraphs 1 to 17, wherein contacting the plastic feedstock with the catalyst composition is at a temperature of about 500° C. to about 600° C.

[0091] Paragraph 19. The process of any one of Paragraphs 1-17, wherein the contacting of the plastic feedstock with the catalyst composition is at a temperature of about 450°C, about 460°C, about 470°C, about 480°C, about 490°C, about 500°C, about 510°C, about 520°C, about 530°C, about 540°C, about 550°C, about 560°C, about 570°C, about 580°C, about 590°C, about 600°C, about 610°C, about 620°C, about 630°C, about 640°C, or about 650°C.

[0092] Paragraph 20. The process of any one of Paragraphs 1 to 19, wherein the plastic feedstock comprises at least one of polyolefins, polyethylene, polypropylene, polystyrene, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyamides, polycarbonates, polyurethanes, polyesters, natural and synthetic rubber, tires, filled polymers, composites, plastic alloys, and plastics dissolved in a solvent.

[0093] Paragraph 21. The process of paragraph 20, wherein the plastic feedstock comprises polyethylene dissolved in a solvent.

[0094] Paragraph 22. The process of Paragraph 21, wherein the plastic feedstock comprises polypropylene dissolved in a solvent.

[0095] Paragraph 23. The process of any one of Paragraphs 1 to 22, wherein the at least one olefin is selected from ethylene, propylene, and butene.

[0096] Paragraph 24. The process of Paragraph 23, wherein the process converts the plastic feedstock to greater than about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, or about 70% by weight of ethylene, propylene, and butenes.

[0097] Paragraph 25. The process of Paragraph 23, wherein the process converts the plastic feedstock to greater than about 20%, about 25%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, or about 70% by weight of propylene.

[0098] Paragraph 26. The process of any one of Paragraphs 1 to 22, wherein the at least one aromatic compound is selected from benzene, toluene, and xylene.

[0099] Paragraph 27. The process of any one of Paragraphs 1 to 26, wherein the period of time sufficient to convert at least a portion of the plastic feedstock to at least one or more olefins and aromatic compounds is a space time in the range of about 0.2 to about 10 hours.

[0100] Paragraph 28. The process of any one of Paragraphs 1 to 27, wherein the conical spouted bed reactor is equipped with a draft tube and a restrictor.

[0101] Paragraph 29. A conical spouted bed reactor is O gas inlet opening, and D C The diameter of the cylindrical portion of the conical spouted bed reactor is D G and the draft tube has a diameter of H G 29. The process of paragraph 28, having a distance from the top of the draft tube to the bottom of the draft tube of.

[0102] Paragraph 30.H G However, about 3 to 4 x D O 30. The process of paragraph 29, wherein

[0103] Paragraph 31.H G However, approximately 1.5 to 2.5 x D O 31. The process according to paragraph 30, wherein

[0104] Paragraph 32.H G But about 2×D O 32. The process of paragraph 31, wherein

[0105] Paragraph 33.D G But about 3×D O ~about 0.7D C 33. The process of any one of paragraphs 29 to 32, wherein

[0106] Paragraph 34.D G However, about 4 to about 6 x D O 34. The process of paragraph 33, wherein

[0107] Paragraph 35.D G However, about 5×D O

[0113] While certain embodiments have been illustrated and described, it is to be understood that changes and modifications can be made therein by those skilled in the art without departing from the technology in its broader aspects as defined in the following claims.

[0108] The embodiments illustratively described herein may be suitably practiced in the absence of any element(s), limitation(s) not specifically disclosed herein. Thus, for example, terms such as "comprising", "including", "containing" and the like should be read expansively and without limitation. In addition, the terms and expressions used herein are used as terms of description and not of limitation, and in the use of such terms and expressions, there is no intention to exclude any equivalents of the shown and described features or portions thereof, but it is recognized that various modifications are possible within the scope of the claimed technology. In addition, the phrase "consisting essentially of" will be understood to include those elements specifically recited, as well as those additional elements that do not materially affect the basic and novel features of the claimed technology. The phrase "consisting of" excludes any elements not specified.

[0109] The present disclosure is not limited with respect to the specific embodiments described in this application. As will be apparent to those skilled in the art, many modifications and variations can be made without departing from the spirit and scope of the present invention. In addition to those recited herein, functionally equivalent methods and compositions within the scope of the present disclosure will be apparent to those skilled in the art from the foregoing description. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that the present disclosure is not limited to specific methods, reagents, compounds, or compositions, which may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

[0110] Additionally, when features or aspects of the disclosure are described in terms of a Markush group, one of skill in the art will recognize that the disclosure is also thereby described in terms of any individual members or subgroups of members of the Markush group.

[0111] As will be understood by those skilled in the art, for any and all purposes, especially in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations thereof. It can be easily recognized that any recited range fully describes and allows for the same range to be subdivided into at least two, three, four, five, ten, etc. As a non-limiting example, each range discussed herein can be easily subdivided into a lower third, a middle third, an upper third, etc. Also, as will be understood by those skilled in the art, all terms such as "up to," "at least," "greater than," "less than," etc. refer to ranges that include the numbers recited and can then be subdivided into the subranges discussed above. Finally, as will be understood by those skilled in the art, a range includes each individual member.

[0112] All publications, patent applications, issued patents, and other documents referenced herein are incorporated by reference as if each individual publication, patent application, issued patent, or other document was specifically and individually indicated to be incorporated by reference in its entirety. Definitions contained in the descriptions incorporated by reference are excluded to the extent that they contradict definitions in this disclosure.

[0113] Other embodiments are within the scope of the following claims.

Claims

1. 1. A process for producing at least one of olefins and aromatic compounds from a plastic feedstock, the process comprising: contacting a plastic feedstock with a catalyst composition in a conical spouted bed reactor at a temperature of about 450°C to about 650°C for a period of time sufficient to convert at least a portion of the plastic feedstock to at least one or more olefins and aromatic compounds; The process wherein the catalyst composition comprises greater than about 40% w / w ZSM-5, based on the total weight of the catalyst composition.

2. 10. The process of claim 1, wherein the catalyst composition comprises greater than about 45% w / w ZSM-5, based on the total weight of the catalyst composition.

3. 10. The process of claim 1, wherein the catalyst composition comprises about 45% w / w to about 80% w / w ZSM-5, based on the total weight of the catalyst composition.

4. 10. The process of claim 1, wherein the catalyst composition comprises particles having a size ranging from about 0.05 mm to about 5 mm.

5. 10. The process of claim 1, wherein the catalyst composition comprises particles having a size of from about 0.8 mm to about 5 mm.

6. The catalyst composition comprises about 5% w / w to about 15% w / w of P based on the total weight of the composition. ２ O ５ 2. The process of claim 1, comprising:

7. The catalyst composition comprises less than about 40% w / w Al, based on the total weight of the composition. ２ O ３ 2. The process of claim 1, comprising:

8. 10. The process of claim 1, wherein the ZSM-5 has a crystallite size of less than about 0.4 microns.

9. 10. The process of claim 1, wherein the catalyst composition is formed by spray drying, extrusion, or bead formation methods.

10. 10. The process of claim 9, wherein the bead formation method is agglomeration.

11. 10. The process of claim 1, wherein the ZSM-5 is combined with an active matrix within particles.

12. 10. The process of claim 1, wherein the ZSM-5 is combined with the active matrix as separate particles.

13. 10. The process of claim 1, wherein the ZSM-5 is combined with one or more zeolites selected from ZSM-11, faujasite, mordenite, and beta.

14. 14. The process of claim 13, wherein the combination of ZSM-5 and one or more zeolites promotes the thermal cracking of polymers.

15. 15. The process of claim 14, wherein the ZSM-5 is combined as separate particles with one or more Y-type zeolites selected from zeolite Y, ultrastable Y zeolite (USY), rare earth exchanged Y (REY), rare earth exchanged USY (REUSY), dealuminated Y (DeAIY), and superhydrophobic Y (UHPY).

16. 10. The process of claim 1, wherein contacting the plastic feedstock with the catalyst composition is at a temperature of about 500°C to about 600°C.

17. 10. The process of claim 1, wherein the plastic feedstock comprises at least one of polyolefins, polyethylene, polypropylene, polystyrene, polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyamides, polycarbonates, polyurethanes, polyesters, natural and synthetic rubbers, tires, filled polymers, composites, plastic alloys, and plastics dissolved in a solvent.

18. 18. The process of claim 17, wherein the plastic feedstock comprises polyethylene dissolved in a solvent.

19. 20. The process of claim 17, wherein the plastic feedstock comprises polypropylene dissolved in a solvent.

20. 10. The process of claim 1, wherein the at least one olefin is selected from ethylene, propylene, and butene.

21. 21. The process of claim 20, wherein the process converts the plastic feedstock to greater than about 35% by weight ethylene, propylene, and butenes.

22. 21. The process of claim 20, wherein the process converts the plastic feedstock to greater than about 20% by weight propylene.

23. 10. The process of claim 1, wherein the at least one aromatic compound is selected from benzene, toluene, and xylene.

24. 10. The process of claim 1, wherein the period of time sufficient to convert at least a portion of the plastic feedstock to at least one or more olefins and aromatics is a space time ranging from about 0.2 to about 10 hours.

25. 10. The process of claim 1, wherein the conical spouted bed reactor is equipped with a draft tube and a restrictor.

26. The conical spouted bed reactor is Ｏ gas inlet opening, and D Ｃ the diameter of the cylindrical portion of the conical spouted bed reactor is D Ｇ and the draft tube has a diameter of H Ｇ 26. The process of claim 25, wherein the distance from the top of the draft tube to the bottom of the draft tube is

27. H Ｇ However, about 3 to about 4 x D Ｏ 27. The process of claim 26, wherein

28. H Ｇ However, approximately 1.5 to 2.5 x D Ｏ 28. The process of claim 27, wherein

29. H Ｇ But about 2 x D Ｏ 29. The process of claim 28, wherein

30. D Ｇ But about 3 x D Ｏ ~about 0.7D Ｃ 27. The process of claim 26, wherein

31. D Ｇ However, about 4 to about 6 x D Ｏ 31. The process of claim 30, wherein:

32. D Ｇ But about 5 x D Ｏ 32. The process of claim 31 , wherein

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