WO2023279022A1

WO2023279022A1 - Methods for treatment of mixed plastic waste pyrolysis oil

Info

Publication number: WO2023279022A1
Application number: PCT/US2022/073256
Authority: WO
Inventors: Robert Charles Schucker; Fabrice Cuoq; Kadek Yulia Kesuma Wardhani SUMPENA; Kae Wong
Original assignee: Sabic Global Technologies B.V.
Priority date: 2021-06-29
Filing date: 2022-06-29
Publication date: 2023-01-05
Also published as: CN117881764A

Abstract

Systems and methods for pretreating a raw mixed plastic waste pyrolysis oil using a solid adsorbent, a solid acid, a solid base and/or an ion exchange resin and then processing the pretreated mixed plastic waste pyrolysis oil by hydrotreating processes.

Description

METHODS FOR TREATMENT OF MIXED PLASTIC WASTE PYROLYSIS OIL

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of and priority to U.S. Provisional Application No.

63/202,891, filed on June 29, 2021, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] The present disclosure generally relates to systems and methods for processing mixed plastic waste pyrolysis oil. More specifically, the present disclosure relates to systems and methods for processing mixed plastic waste pyrolysis oil to produce a feedstock that is usable for a refinery unit, such as a hydrotreater, or a hydrocracker, or a combination thereof.

BACKGROUND

[0003] Pyrolysis oil (pyoil) from the mixed plastic waste is emerging as an alternative feedstock via chemical recycling. Pyoil contains several contaminants, such as diolefins, heavies, chlorides, nitrogenates, and oxygenates. Further processing of pyoil in a steam cracker requires pretreatment of the raw material to remove those contaminants. One way of processing the pyoil is to send it to a hydrotreater unit to convert the diolefins into saturate components, nitrogenates into ammonia, oxygenates into water, carbon monoxide or carbon dioxide, and organic chlorinated components into hydrogen chlorides. Ammonia, water, and hydrogen chlorides can then be removed after the hydrotreater by passing these streams through a stripper or caustic extraction column. Saturated components are not harmful to the steam cracker and are not further removed. The purified stream is then subjected to cracking. One drawback of this process is that the hydrotreater catalyst tends to coke rapidly due to heavy components. Another drawback is that such a process requires a large quantity of hydrogen and a large reactor due to the high level of contamination present in the raw pyoil.

SUMMARY

[0004] To address these shortcomings in the art, Applicant has developed systems and methods for pretreating raw mixed plastic waste pyrolysis oil. Also, provided here are systems and methods for processing the pretreated mixed plastic waste pyrolysis oil by hydrotreating processes. Products formed from the hydrotreating of the pretreated mixed plastic waste pyrolysis oil can also be subject to further hydrocracking and distillation.

[0005] In certain embodiments, the method for pretreating the raw mixed plastic waste pyrolysis oil includes the following steps: supplying a raw mixed plastic pyrolysis oil containing at least one contaminant to a reaction vessel, contacting the raw mixed plastic waste pyrolysis oil with at least one of a solid acid or a solid alkali in the reaction vessel, causing deposition of a portion of the at least one contaminant from the raw mixed plastic waste pyrolysis oil onto the at least one of the solid acid or the solid alkali, and separating the at least one of the solid acid or the solid alkali containing deposition of the portion of the at least one contaminant from the raw mixed plastic waste pyrolysis oil to produce a pre-treated mixed plastic waste pyrolysis oil. The contaminant in the raw mixed plastic pyrolysis oil can be one or more of diolefm compounds, oxygen compounds, nitrogen compounds, or chloride compounds. The step of separating the at least one of the solid acid or the solid alkali containing deposition of the portion of the at least one contaminant from the raw mixed plastic waste pyrolysis oil occurs by one or more of filtration, centrifugation, settling, or hydrocyclonization. The solid acid, the solid alkali, or both can be present in the form of pellets. A solid acid or a solid alkali in the reaction vessel can be positioned in a fixed bed arrangement. In certain embodiments, the reaction vessel includes a fluidized bed unit. The fluidized bed unit can be an ebullated bed unit.

[0006] In an embodiment, the systems and methods for pretreating the raw mixed plastic waste pyrolysis oil include the use of the solid acid, the solid alkali, or both in the form of either an anionic or cationic ion exchange resin or both. Embodiments can further include regeneration of the anionic or cationic ion exchange resin. In one aspect, the method includes supplying the at least one of the solid acid or the solid alkali with the at least one contaminant to a regeneration unit, calcining the at least one of the solid acid or the solid alkali with the at least one contaminant in the regeneration unit, and returning at least one of the calcined solid acid or calcined solid alkali to the reaction vessel.

[0007] Certain embodiments of methods for processing the raw mixed plastic waste pyrolysis oil includes the following steps: supplying a raw mixed plastic pyrolysis oil containing at least one contaminant to a reaction vessel, contacting the raw mixed plastic waste pyrolysis oil with at least one of a solid acid or a solid alkali in the reaction vessel, causing deposition of the at least one contaminant from the raw mixed plastic waste pyrolysis oil onto the at least one of the solid acid or the solid alkali, separating the at least one of the solid acid or the solid alkali with the at least one contaminant from the raw mixed plastic waste pyrolysis oil to produce a pre-treated mixed plastic waste pyrolysis oil, introducing the pre-treated mixed plastic waste pyrolysis oil to a hydrotreater, processing the pre-treated mixed plastic waste pyrolysis oil with a hydrotreating catalyst in the hydrotreater, and obtaining a hydrotreated mixed plastic waste pyrolysis oil from the hydrotreater. The contaminant in the raw mixed plastic waste pyrolysis oil is one or more of diolefm compounds, oxygen compounds, nitrogen compounds or chloride compounds. In certain embodiments, the processing of the pre-treated mixed plastic waste pyrolysis oil with the hydrotreating catalyst in the hydrotreater includes converting at least some of the diolefin compounds in the pre-treated mixed plastic waste pyrolysis oil into one or more saturated hydrocarbon compounds. In an aspect, the processing of the pre-treated mixed plastic waste pyrolysis oil with the hydrotreating catalyst in the hydrotreater includes converting at least some of the nitrogen compounds in the pre-treated mixed plastic waste pyrolysis oil into one or more ammonia-containing compounds, or at least some of the oxygen compounds into water, carbon monoxide or carbon dioxide, or both.

[0008] Certain embodiments of methods for pretreating the raw mixed plastic waste pyrolysis oil includes the following steps: obtaining a raw mixed plastic pyrolysis oil containing one or more of diolefin compounds, oxygen compounds, nitrogen compounds, and chloride compounds, contacting the raw mixed plastic pyrolysis oil with a solid adsorbent, and causing adsorption of a portion of the one or more diolefin compounds, oxygen compounds, nitrogen compounds, and chloride compounds from the raw mixed plastic pyrolysis oil on a plurality of pores in the solid adsorbent, thereby producing a pre-treated mixed plastic waste pyrolysis oil. The solid adsorbent can be one or more of activated carbon, aluminosilicate, and silica. This pre-treated mixed plastic waste pyrolysis oil contains reduced amounts of the one or more of diolefin compounds, oxygen compounds, nitrogen compounds, and chloride compounds as compared to the raw mixed plastic pyrolysis oil. The method further includes the steps of separating the pre-treated mixed plastic waste pyrolysis oil from the solid adsorbent, introducing the pre-treated mixed plastic waste pyrolysis oil to a hydrotreater, processing the pre-treated mixed plastic waste pyrolysis oil with a hydrotreating catalyst in the hydrotreater, and obtaining a hydrotreated mixed plastic waste pyrolysis oil from the hydrotreater. This hydrotreated mixed plastic waste pyrolysis oil contains reduced amounts of the one or more of diolefin compounds, oxygen compounds, and nitrogen compounds as compared to the pre-treated mixed plastic waste pyrolysis oil.

[0009] In certain embodiments, the method includes the step of separating the pre-treated mixed plastic waste pyrolysis oil from the solid adsorbent through centrifugation, filtration, settling, or hydrocyclonization. In certain embodiments, the raw mixed plastic pyrolysis oil is in contact with the solid adsorbent inside a fixed bed unit. In certain embodiments, the raw mixed plastic pyrolysis oil is in contact with the solid adsorbent inside a fluidized bed unit. The fluidized bed unit can be an ebullated bed unit.

[0010] Embodiments of a system include a reaction vessel in which the solid adsorbent is present in a ratio of solid to liquid components ranging from about 0.2 to about 90 volume percent. The reaction vessel can be a fluidized bed unit, such as an ebullated bed unit, with the solid adsorbent occupying from about 20 to about 30 volume percent.

[0011] Certain embodiments of methods for pretreating the raw mixed plastic waste pyrolysis oil includes the following steps: obtaining a raw mixed plastic pyrolysis oil containing one or more of diolefin compounds, oxygen compounds, nitrogen compounds, and chloride compounds, contacting the raw mixed plastic pyrolysis oil with activated carbon, causing adsorption of a portion of the one or more diolefin compounds, oxygen compounds, nitrogen compounds, and chloride compounds from the raw mixed plastic pyrolysis oil on a plurality of pores in the activated carbon, thereby producing a pre-treated mixed plastic waste pyrolysis oil, and separating the pretreated mixed plastic waste pyrolysis oil from the activated carbon. This pre-treated mixed plastic waste pyrolysis oil contains reduced amounts of the one or more of diolefin compounds, oxygen compounds, nitrogen compounds, and chloride compounds as compared to the raw mixed plastic pyrolysis oil. In certain embodiments, the amount of nitrogen compounds in the pre-treated mixed plastic waste pyrolysis oil is reduced by at least about 40% as compared to the amount of nitrogen compounds in the raw mixed plastic pyrolysis oil. In certain embodiments, the amount of nitrogen compounds in the pre-treated mixed plastic waste pyrolysis oil is reduced by at least about 50%, or about 60%, or about 70%, or about 80%, or about 95% as compared to the amount of nitrogen compounds in the raw mixed plastic pyrolysis oil. In certain embodiments, the amount of oxygen compounds in the pre-treated mixed plastic waste pyrolysis oil is reduced by at least about 20% as compared to the amount of oxygen compounds in the raw mixed plastic pyrolysis oil. In certain embodiments, the amount of oxygen compounds in the pre-treated mixed plastic waste pyrolysis oil is reduced by at least about 30%, or about 40%, or about 50%, or about 60%, or about 70%, or about 80%, or about 95% as compared to the amount of oxygen compounds in the raw mixed plastic pyrolysis oil.

[0012] Certain embodiments of methods further include the steps of: introducing the pre-treated mixed plastic waste pyrolysis oil to a hydrotreater, processing the pre-treated mixed plastic waste pyrolysis oil with a hydrotreating catalyst in the hydrotreater, and obtaining a hydrotreated mixed plastic waste pyrolysis oil from the hydrotreater. This hydrotreated mixed plastic waste pyrolysis oil contains reduced amounts of the one or more of diolefin compounds, oxygen compounds, and nitrogen compounds as compared to the pre-treated mixed plastic waste pyrolysis oil.

[0013] Still other aspects and advantages of these exemplary embodiments and other embodiments, are discussed in detail herein. Moreover, it is to be understood that both the foregoing information and the following detailed description provide merely illustrative examples of various aspects and embodiments, and are intended to provide an overview or framework for understanding the nature and character of the claimed aspects and embodiments. Accordingly, these and other objects, along with advantages and features of the present disclosure, will become apparent through reference to the following description and the accompanying drawings. Furthermore, it is to be understood that the features of the various embodiments described herein are not mutually exclusive and may exist in various combinations and permutations.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

[0015] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present disclosure, are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure, and together with the detailed description, serve to explain principles of the embodiments discussed herein. No attempt is made to show structural details of this disclosure in more detail than may be necessary for a fundamental understanding of the embodiments discussed herein and the various ways in which they may be practiced. According to common practice, the various features of the drawings discussed below are not necessarily drawn to scale. Dimensions of various features and elements in the drawings may be expanded or reduced to more clearly illustrate embodiments of the disclosure.

[0016] FIG. l is a schematic flowchart for a method of processing mixed plastic waste pyrolysis oil, according to an embodiment.

[0017] FIG. 2 is an illustration of an ebullated bed unit for processing mixed plastic waste pyrolysis oil, according to an embodiment.

[0018] FIG. 3 is a schematic flowchart for a method of processing mixed plastic waste pyrolysis oil, according to an embodiment. [0019] FIG. 4 is a graphical representation of the reduction in the oxygen compounds, nitrogen compounds, and chloride compounds in the mixed plastic waste pyrolysis oil, using different solid adsorbents, according to an embodiment.

DETAILED DESCRIPTION

[0020] The present disclosure describes various embodiments related to processes, devices, and systems for pretreating the raw mixed plastic waste pyrolysis oil. Also, provided here are systems and methods for processing the pretreated raw mixed plastic waste pyrolysis oil by subjecting it to further hydrotreating processes. Further embodiments may be described and disclosed.

[0021] In the following description, numerous details are set forth in order to provide a thorough understanding of the various embodiments. In other instances, well-known processes, devices, and systems may not have been described in particular detail in order not to unnecessarily obscure the various embodiments. Additionally, illustrations of the various embodiments may omit certain features or details in order to not obscure the various embodiments.

[0022] The description may use the phrases “in some embodiments,” “in various embodiments,” “in an embodiment,” or “in embodiments,” which may each refer to one or more of the same or different embodiments. Furthermore, the terms “comprising,” “including,” “having,” and the like, as used with respect to embodiments of the present disclosure, are synonymous.

[0023] The term “about” or “approximately” are defined as being close to as understood by one of ordinary skill in the art. In one non-limiting embodiment, the terms are defined to be within 10%, preferably within 5%, more preferably within 1%, and most preferably within 0.5%.

[0024] The terms “reducing,” “reduced,” or any variation thereof, when used in the claims and/or the specification includes any measurable decrease or complete inhibition to achieve a desired result. [0025] The use of the words “a” or “an” when used in conjunction with any of the terms “comprising,” “including,” “containing,” or “having,” in the claims or the specification may mean “one,” but it is also consistent with the meaning of “one or more,” “at least one,” and “one or more than one ” The terms “wt.%”, “vol.%”, or “mol.%” refers to a weight, volume, or molar percentage of a component, respectively, based on the total weight, the total volume of material, or total moles, that includes the component. In a non-limiting example, 10 grams of component in 100 grams of the material is 10 wt.% of component.

[0026] The words “comprising” (and any form of comprising, such as “comprise” and “comprises”), “having” (and any form of having, such as “have” and “has”), “including” (and any form of including, such as “includes” and “include”) or “containing” (and any form of containing, such as “contains” and “contain”) are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

[0027] Disclosed here are systems and methods for pretreating the mixed plastic waste pyrolysis oil. Pre-treatment of the pyrolysis oil will reduce contaminants level in the hydrotreater feed. This step of pre-treatment assists with the reduction of hydrogen consumption in the hydrotreater. This step of pre-treatment also reduces one or more of diolefin compounds, oxygen compounds, nitrogen compounds, or chloride compounds in the downstream processing units. [0028] FIG. 1 is a schematic flowchart for a method 100 of processing mixed plastic waste pyrolysis oil, according to an embodiment. A raw mixed plastic pyrolysis oil stream 102 is supplied to a reaction vessel 104. This raw mixed plastic pyrolysis oil stream 102 contains one or more contaminants. The contaminant in the raw mixed plastic pyrolysis oil can be one or more of diolefin compounds, oxygen compounds, nitrogen compounds, or chloride compounds. Chloride compounds include chloride salts and organic chloride compounds, such as chlorinated hydrocarbons, like chlorethanol or chlorobenzonitrile. Oxygen compounds include organic hydrocarbons, like hexanoic acid or phenols. Nitrogen compounds include nitrides, nitrates, and organic compounds, such as nitrogenated hydrocarbons, tridecanenitrile or indoles.

[0029] The raw mixed plastic waste pyrolysis oil stream 102 is brought into contact with a solid acid or a solid alkali in the reaction vessel 104, causing deposition of a portion of the contaminant from the raw mixed plastic waste pyrolysis oil onto the solid acid or the solid alkali. The solid alkali can be any of Group I compounds or Group 2 compounds. The solid alkali can be hydroxides of Group I or Group 2 elements, such as lithium hydroxides, sodium hydroxides, potassium hydroxides, calcium hydroxides, or magnesium hydroxides. The solid alkali can be halides of Group I or Group 2 elements, such as sodium bromide, potassium bromide, calcium chloride, or magnesium chloride. The solid alkali can be oxides of Group I or Group 2 elements, such as potassium oxides, calcium oxides, or magnesium oxides. Solid acids can include certain silica aluminas and sulfated zirconia. The solid acid, the solid alkali, or both can take the form of, but is not limited to, extruded, molded or other formed solid pellets, blocks, tablets, powders, granules, flakes, or the formed solids may then be comminuted or formed into powders, granules or flakes. The solid acid, the solid alkali, or both can also be supported on a carrier and presented in the reaction vessel. In an embodiment, the solid acid, the solid alkali, or both are present in the form of pellets inside the reaction vessel.

[0030] In certain embodiments, the alkaline extraction of the contaminants from the mixed plastic waste pyrolysis oil can be performed with sodium hydroxides, potassium hydroxides, or ammonium hydroxides, or other strong bases and can be performed in liquid/liquid, in liquid/gaseous, or solid/liquid form. In certain embodiments, the acid extraction of the contaminants from the mixed plastic waste pyrolysis oil can be performed with hydrochloric acid, sulfuric acid, or other strong acids and can be performed in liquid/liquid or liquid/gaseous phases. [0031] The reaction vessel can be one or more of a fixed bed, a moving bed, a fixed stirred unit, or a fluidized bed unit, either placed as a single unit, or as multiple units in series or in parallel to pretreat the raw mixed plastic waste pyrolysis oil stream 102. The fluidized bed unit can be an ebullated bed unit. An example of an ebullated bed unit for the methods and disclosed here is illustrated in FIG. 2.

[0032] Stream 106 containing the solid acid or the solid alkali containing deposition of the portion of the contaminant and the pre-treated mixed plastic waste pyrolysis oil is supplied to a separator 108. The solid acid or the solid alkali containing deposition of the portion of the at least one contaminant is separated from the pre-treated mixed plastic waste pyrolysis oil by one or more of filtration, centrifugation, settling, or hydrocyclonization. The pre-treated mixed plastic waste pyrolysis oil stream 110 is then supplied to other downstream processing units.

[0033] In an embodiment, the systems and methods for pretreating the raw mixed plastic waste pyrolysis oil include the use of the solid acid, the solid alkali, or both in the form of an anionic or cationic ion exchange resin, e.g. with quaternary or sulfonated group, respectively. Embodiments of this method 100 can optionally include the step of regenerating the anionic or cationic ion exchange resin. In this method 100, a stream 112 containing the solid acid, the solid alkali, or both with a portion of the contaminant exits the separator 108 and is supplied to a regeneration unit 114. The solid acid, the solid alkali, or both with the contaminant is subject to calcination in the regeneration unit 114. The calcination temperature is in the range of from about 350 °C to about 1000 °C, or from about 450 °C to about 800 °C. The calcination takes place under conditions sufficient to assure relatively uniform temperature and uniform removal of the deposits of the contaminants. This calcination process can be carried out under atmospheric pressure. After treatment in a regeneration unit 114, the calcined solid acid or calcined solid alkali 116 is returned or recycled to the reaction vessel. Optionally, the solid acid, the solid alkali, or both is washed by a solvent, like THF or methanol or acetone, to remove any soluble materials from the solid acid, the solid alkali, or both before being calcined and/or after calcination. In certain embodiments with the anionic or cationic ion exchange resins, the resins are rinsed with strong bases (like caustic soda) or strong acids (like hydrochloric acid) and regenerated.

[0034] Certain embodiments of methods for processing the raw mixed plastic waste pyrolysis oil include supplying the pre-treated mixed plastic waste pyrolysis oil stream 110 to a hydrotreater. Here, the pre-treated mixed plastic waste pyrolysis oil is brought into contact with a hydrotreating catalyst in the hydrotreater. The processing of the pre-treated mixed plastic waste pyrolysis oil with the hydrotreating catalyst in the hydrotreater includes converting at least some of the diolefm compounds in the pre-treated mixed plastic waste pyrolysis oil into one or more saturated hydrocarbon compounds. In an aspect, the processing of the pre-treated mixed plastic waste pyrolysis oil with the hydrotreating catalyst in the hydrotreater includes converting at least some of the nitrogen compounds in the pre-treated mixed plastic waste pyrolysis oil into one or more ammonia-containing compounds, or at least some of the oxygen compounds into water, carbon monoxide or carbon dioxide, or both. The hydrotreated mixed plastic waste pyrolysis oil from the hydrotreater may then be subject to hydrocracking and/or distillation.

[0035] FIG. 2 is an illustration of an ebullated bed unit 200 for processing mixed plastic waste pyrolysis oil, according to an embodiment. It is a fluidized-bed multi-phase unit with continuous mixing of raw mixed plastic pyrolysis oil stream and solid adsorbent compositions. Examples of solid adsorbent compositions include and are not limited to activated carbon, solid alkali, solid acid, clays, silica, or combinations thereof.

[0036] The solid adsorbent compositions are delivered to the ebullated bed unit 200 via an adsorbent inlet 202. The raw mixed plastic pyrolysis oil stream is supplied via a feed inlet 204 to the ebullated bed unit 200. The solid adsorbent compositions are maintained in a fluidized state through the upward lift of liquid phase components — raw mixed plastic pyrolysis oil stream supplied via a feed inlet 204 and a recycle stream via recycle inlet 220. These liquid phase components are distributed across the solid adsorbent bed through a distributor and grid plate 206. The height of the adsorbent layers inside the ebullated bed unit 200 is determined by the height of the settled adsorbent region 210 and the expanded adsorbent region 208, which are controlled by the rate of flow of the liquid phase components. The pre-treated mixed plastic waste pyrolysis oil is removed from the ebullated bed unit 200 via a product exit 212 situated in an adsorbent-free zone above the expanded adsorbent region 208. Fresh solid adsorbents can be added via the adsorbent inlet 202 and a portion of the used solid adsorbents can be withdrawn via an adsorbent exit 222. A portion of the pre-treated mixed plastic waste pyrolysis oil is removed via the recycle exits 214 before being passed through the recycle conduit 216 to the recycle pump 218. The recycled mixed plastic pyrolysis oil stream is supplied back via recycle inlet 220 to the ebullated bed unit 200. Operating conditions are usually optimized based on the feed and the desired products. Residence time can vary from one hour to 24 hours and pressure is maintained at atmospheric pressure with temperature ranging from 5 °C to 50 °C and loading ranging from 20 to 30 volume percent.

[0037] Certain embodiments of systems for pretreating the raw mixed plastic waste pyrolysis oil include a reaction vessel in fluid communication with a separator. The reaction vessel is configured to receive a solid adsorbent composition and a raw mixed plastic pyrolysis oil containing one or more of diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds. This reaction vessel is configured to cause adsorption of a portion of the one or more diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds from the raw mixed plastic pyrolysis oil on a plurality of pores in the solid adsorbent, thereby producing a pretreated mixed plastic waste pyrolysis oil. The reaction vessel can be one or more of a fixed bed, a moving bed, a fixed stirred unit, or a fluidized bed unit, either placed as a single unit, or as multiple units in series or in parallel to pretreat the raw mixed plastic waste pyrolysis oil stream. The fluidized bed unit can be an ebullated bed unit. An example of an ebullated bed unit for the methods and disclosed here is illustrated in FIG. 2. Embodiments of a system include a reaction vessel in which the solid adsorbent is present in a ratio of solid to liquid components from about 0.2 to about 90 volume percent. The reaction vessel can be a fluidized bed unit, such as an ebullated bed unit, with the solid adsorbent occupying from about 20 to about 30 volume percent. The solid adsorbent can be one or more of activated carbon, aluminosilicate, and silica. This pre-treated mixed plastic waste pyrolysis oil contains reduced amounts of the one or more of diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds as compared to the raw mixed plastic pyrolysis oil.

[0038] The separator is configured to separate the pre-treated mixed plastic waste pyrolysis oil from the used solid adsorbent. In certain embodiments, the separator is one or more of a centrifugation unit, a filtration unit, a settling vessel, or a hydrocyclone unit. In certain embodiments, the separator is in fluid communication with a hydrotreater. The hydrotreater is configured to process the pre-treated mixed plastic waste pyrolysis oil in the presence of a hydrotreating catalyst to produce a hydrotreated mixed plastic waste pyrolysis oil. This hydrotreated mixed plastic waste pyrolysis oil contains reduced amounts of the one or more of diolefin compounds, oxygen compounds, nitrogen compounds, and chloride compounds as compared to the pre-treated mixed plastic waste pyrolysis oil.

[0039] During an adsorption process based on solid adsorbent compositions, the reaction vessel can be operated in fixed bed or batch process. In an embodiment of a fixed bed operation, the raw mixed plastic pyrolysis oil is allowed to flow over a fixed bed of granular adsorbent. Once the granular adsorbent is saturated with the contaminants, it can be regenerated externally or disposed according to economics. In an embodiment of batch process, the solid adsorbent is added to the raw mixed plastic pyrolysis oil in a stirred tank as a reaction vessel. And upon termination of the reaction, the pre-treated mixed plastic waste pyrolysis oil is separated from the solid adsorbent via centrifugation, filtration, hydrocylcone, or other separation methods.

[0040] During an adsorption process based on gas/liquid extraction, gaseous HC1 or NH3 is passed into the reaction vessel that contains the raw mixed plastic pyrolysis oil. This leads to solid deposition of acid and nitrogenates components, respectively. Solids are then removed mechanically from the pre-treated mixed plastic waste pyrolysis oil via centrifugation, filtration, hydrocylcone or other separation methods.

[0041] During an adsorption process based on liquid/liquid extraction, an immiscible extraction solvent is added to the feed and the mixture is stirred well to promote transfer of contaminants, e g., at the boundary layer, from the raw mixed plastic pyrolysis oil into the extract phase. The raffinate phase is the pre-treated mixed plastic waste pyrolysis oil. The extraction solvent can be an organic solvent or water. Separation is performed either by centrifugation or settling (that can be enhanced with an emulsion vessel). [0042] FIG. 3 is a schematic flowchart for a method 300 of processing mixed plastic waste pyrolysis oil, according to an embodiment. A raw mixed plastic pyrolysis oil stream 302 containing one or more of diolefin compounds, oxygen compounds, nitrogen compounds, and chloride compounds is brought into contact the raw mixed plastic pyrolysis oil with activated carbon 304, causing adsorption of a portion of the one or more diolefin compounds, oxygen compounds, nitrogen compounds, and chloride compounds from the raw mixed plastic pyrolysis oil on a plurality of pores in the activated carbon. The resulting pre-treated mixed plastic waste pyrolysis oil stream 306 is supplied to a separator 308 to separate the pre-treated mixed plastic waste pyrolysis oil from the activated carbon containing an adsorbed portion of the one or more diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds. The stream 312 of activated carbon containing an adsorbed portion of the one or more diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds exits the separator and can be processed in a regeneration unit. This pre-treated mixed plastic waste pyrolysis oil stream 310 contains reduced amounts of the one or more of diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds as compared to the raw mixed plastic pyrolysis oil. In certain embodiments, the amount of nitrogen compounds in the pre-treated mixed plastic waste pyrolysis oil is reduced by at least about 40% as compared to amount of nitrogen compounds in the raw mixed plastic pyrolysis oil. In certain embodiments, the amount of nitrogen compounds in the pre treated mixed plastic waste pyrolysis oil is reduced by at least about 50%, or about 60%, or about 70%, or about 80%, or about 95% as compared to the amount of nitrogen compounds in the raw mixed plastic pyrolysis oil. In certain embodiments, the amount of oxygen compounds in the pre treated mixed plastic waste pyrolysis oil is reduced by at least about 20% as compared to the amount of oxygen compounds in the raw mixed plastic pyrolysis oil. In certain embodiments, the amount of oxygen compounds in the pre-treated mixed plastic waste pyrolysis oil is reduced by at least about 30%, or about 40%, or about 50%, or about 60%, or about 70%, or about 80%, or about 95% as compared to the amount of oxygen compounds in the raw mixed plastic pyrolysis oil. [0043] Certain embodiments of methods further include introducing the pre-treated mixed plastic waste pyrolysis oil stream 310 to a hydrotreater 314, processing the pre-treated mixed plastic waste pyrolysis oil with a hydrotreating catalyst in the hydrotreater; and obtaining a hydrotreated mixed plastic waste pyrolysis oil 316 from the hydrotreater. This hydrotreated mixed plastic waste pyrolysis oil contains reduced amounts of the one or more of diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds as compared to the pre-treated mixed plastic waste pyrolysis oil.

EXAMPLES

[0044] Various examples provided below illustrate selected aspects of the various methods of using solid adsorbents to pretreat mixed plastic waste pyrolysis oil.

Example 1

[0045] About 50 ml of mixed plastic waste pyrolysis oil was passed through an adsorbent bed of 120 grams of activated carbon, using a pyoil density of 0.78 grams per liter (g/1). The weight ratio of pyoil to adsorbent was 1 to 3. The amount of reduction of chloride compounds, oxygen compounds, and nitrogen compounds, measured in parts per million weight (ppmw) are presented in Table 1. Table 1.

Example 2

[0046] FIG. 4 is a graphical representation of the reduction in the oxygen compounds, nitrogen compounds, and chloride compounds in the mixed plastic waste pyrolysis oil, using selected solid adsorbents, according to an embodiment. Those results have been obtained in batch process using these solid adsorbents at about 1.9 wt% and 24 hours contact time at 20 °C. After mixing, the pyoil was filtered over a 0.2 um syringe filter and further analyzed. The select adsorbents include silica product 1 (labeled as 1 in FIG. 4), clay product 1 (labeled as 2 in FIG. 4), ion exchange resin (labeled as 3 in FIG. 4), zeolite (labeled as 4 in FIG. 4), clay product 2 (labeled as 5 in FIG. 4), activated carbon product 1 (labeled as 6 in FIG. 4), activated carbon product 2 (labeled as 7 in FIG. 4), silica product 2 (labeled as 8 in FIG. 4), washed activated carbon (labeled as 9 in FIG. 4), clay product 3 (labeled as 10 in FIG. 4), and calcium oxide (labeled as 11 in FIG. 4). Example 3

[0047] Table 2 presents the reduction in the oxygen compounds, nitrogen compounds, and chloride compounds in the mixed plastic waste pyrolysis oil when calcium oxide at 900 °C for 8 hours was used as an adsorbent in a batch reactor process at different weight percentages. Removal does not increase with increasing amount of adsorbent due to specific adsorption isotherm leading to high load of contaminants on the adsorbent under strong pressure of contaminants but low load of contaminants on the adsorbent under low pressure of contaminant. Table 2

Example 4

[0048] Table 3 presents the reduction in the oxygen compounds, nitrogen compounds, and chloride compounds in the mixed plastic waste pyrolysis oil when a strong ion exchange resin of class I was used as an adsorbent in a batch reactor process at different weight percentages.

Table 3

Example 5

[0049] Table 4 presents the reduction in the oxygen compounds, nitrogen compounds, and chloride compounds in the mixed plastic waste pyrolysis oil when a strong cationic exchange resin of class I (solid acid)) was used as an adsorbent in a batch reactor process at different weight percentages. Removal of chloride and oxygen is poorly affected by the strong cation exchange resins as those organic contaminants have poor interaction with this substrate.

Table 4

Example 6

Table 5 presents the reduction in the oxygen compounds, nitrogen compounds, and chloride compounds in the mixed plastic waste pyrolysis oil when polystyrenic macroporous adsorbent resin was used as an adsorbent in a batch reactor process at different weight percentages.

Table 5

Example 7

[0050] Table 6 presents the reduction in the oxygen compounds, nitrogen compounds, and chloride compounds in the mixed plastic waste pyrolysis oil when an activated carbon was used as an adsorbent in a batch reactor process at different weight percentages.

Table 6

[0051] When ranges are disclosed herein, ranges from any lower limit may be combined with any upper limit to recite a range not explicitly recited, as well as, ranges from any lower limit may be combined with any other lower limit to recite a range not explicitly recited, in the same way, ranges from any upper limit may be combined with any other upper limit to recite a range not explicitly recited. Additionally, reference to values stated in ranges includes each and every value within that range, even though not explicitly recited. Thus, every point or individual value may serve as its own lower or upper limit combined with any other point or individual value or any other lower or upper limit, to recite a range not explicitly recited.

[0052] Other objects, features and advantages of the disclosure will become apparent from the foregoing figures, detailed description, and examples. It should be understood, however, that the figures, detailed description, and examples, while indicating specific embodiments of the disclosure, are given by way of illustration only and are not meant to be limiting. In further embodiments, features from specific embodiments may be combined with features from other embodiments. For example, features from one embodiment may be combined with features from any of the other embodiments. In further embodiments, additional features may be added to the specific embodiments described herein.

Claims

Claims What is claimed is:

1. A method of pretreating a raw mixed plastic waste pyrolysis oil, the method comprising: supplying a raw mixed plastic pyrolysis oil containing at least one contaminant to a reaction vessel, the contaminant being one or more of diolefin compounds, oxygen compounds, nitrogen compounds, or chloride compounds; contacting the raw mixed plastic waste pyrolysis oil with at least one of a solid acid or a solid alkali in the reaction vessel; causing deposition of a portion of the at least one contaminant from the raw mixed plastic waste pyrolysis oil onto the at least one of the solid acid or the solid alkali; and separating the at least one of the solid acid or the solid alkali containing deposition of the portion of the at least one contaminant from the raw mixed plastic waste pyrolysis oil to produce a pre-treated mixed plastic waste pyrolysis oil.

2. The method of claim 1, wherein separating the at least one of the solid acid or the solid alkali containing deposition of the portion of the at least one contaminant from the raw mixed plastic waste pyrolysis oil occurs by one or more of filtration, centrifugation, settling, or hydrocyclonization.

3. The method of claim 1, wherein the solid acid, the solid alkali, or both are present in the form of pellets.

4. The method of claim 1, wherein the solid acid, the solid alkali, or both include an anionic or cationic ion exchange resin.

5. The method of claim 4, further comprising: regenerating the anionic or cationic ion exchange resin.

6. The method of claim 1, further comprising: supplying the at least one of the solid acid or the solid alkali with the at least one contaminant to a regeneration unit; calcining the at least one of the solid acid or the solid alkali with the at least one contaminant in the regeneration unit; and returning at least one of the calcined solid acid or calcined solid alkali to the reaction vessel.

7. The method of claim 1, wherein the at least one of a solid acid or a solid alkali in the reaction vessel is positioned in a fixed bed arrangement.

8. The method of claim 1, wherein the reaction vessel is a fluidized bed unit.

9. The method of claim 8, wherein the fluidized bed unit is an ebullated bed unit.

10. A method of processing a raw mixed plastic waste pyrolysis oil, the method comprising: supplying a raw mixed plastic pyrolysis oil containing at least one contaminant to a reaction vessel, the contaminant being one or more of diolefin compounds, oxygen compounds, nitrogen compounds, or chloride compounds; contacting the raw mixed plastic waste pyrolysis oil with at least one of a solid acid or a solid alkali in the reaction vessel; causing deposition of the at least one contaminant from the raw mixed plastic waste pyrolysis oil onto the at least one of the solid acid or the solid alkali; separating the at least one of the solid acid or the solid alkali with the at least one contaminant from the raw mixed plastic waste pyrolysis oil to produce a pre-treated mixed plastic waste pyrolysis oil; introducing the pre-treated mixed plastic waste pyrolysis oil to a hydrotreater; processing the pre-treated mixed plastic waste pyrolysis oil with a hydrotreating catalyst in the hydrotreater; and obtaining a hydrotreated mixed plastic waste pyrolysis oil from the hydrotreater.

11. The method of claim 10, wherein processing the pre-treated mixed plastic waste pyrolysis oil with the hydrotreating catalyst in the hydrotreater includes converting: at least some of the diolefm compounds in the pre-treated mixed plastic waste pyrolysis oil into one or more saturated hydrocarbon compounds, at least some of the nitrogen compounds in the pre-treated mixed plastic waste pyrolysis oil into one or more ammonia-containing compounds, and at least some of the oxygen compounds into water, carbon monoxide, or carbon dioxide.

12. A method of removing contaminants from raw mixed plastic waste pyrolysis oil, the method comprising: obtaining a raw mixed plastic pyrolysis oil containing one or more of diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds; contacting the raw mixed plastic pyrolysis oil with a solid adsorbent, the solid adsorbent being one or more of activated carbon, aluminosilicate, and silica; causing adsorption of a portion of the one or more diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds from the raw mixed plastic pyrolysis oil on a plurality of pores in the solid adsorbent, thereby producing a pre-treated mixed plastic waste pyrolysis oil, the pre-treated mixed plastic waste pyrolysis oil containing reduced amounts of the one or more of diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds as compared to the raw mixed plastic pyrolysis oil; separating the pre-treated mixed plastic waste pyrolysis oil from the solid adsorbent; introducing the pre-treated mixed plastic waste pyrolysis oil to a hydrotreater; processing the pre-treated mixed plastic waste pyrolysis oil with a hydrotreating catalyst in the hydrotreater; and obtaining a hydrotreated mixed plastic waste pyrolysis oil from the hydrotreater, the hydrotreated mixed plastic waste pyrolysis oil containing reduced amounts of the one or more of diolefm compounds, oxygen compounds, nitrogen compounds, and chloride compounds as compared to the pre-treated mixed plastic waste pyrolysis oil.

13. The method of claim 12, wherein separating the pre-treated mixed plastic waste pyrolysis oil from the solid adsorbent is conducted through centrifugation, filtration, settling, or hydrocyclonization.

14. The method of claim 12, wherein the raw mixed plastic pyrolysis oil is in contact with the solid adsorbent inside a fixed bed unit.

15. The method of claim 12, wherein the raw mixed plastic pyrolysis oil is in contact with the solid adsorbent inside a fluidized bed unit.

16. The method of claim 15, wherein the fluidized bed unit is an ebullated bed unit.

17. The method of claim 16, wherein the solid adsorbent is present in a ratio of solid to liquid components from about 20 to about 30 volume percent.

18. The method of claim 12, wherein the solid adsorbent is activated carbon.

19. The method of claim 18, wherein an amount of nitrogen compounds in the pre-treated mixed plastic waste pyrolysis oil is reduced by at least about 40 percent as compared to amount of nitrogen compounds in the raw mixed plastic pyrolysis oil.

20. The method of claim 18, wherein an amount of oxygen compounds in the pre-treated mixed plastic waste pyrolysis oil is reduced by at least about 40 percent as compared to amount of oxygen compounds in the raw mixed plastic pyrolysis oil.