Systems and methods for processing pyrolysis oil

Abstract

Systems and methods for treating pyrolysis oil are disclosed. The pyrolysis oil is treated with a sorbent to capture and / or adsorb gum and / or gum precursors and other heteroatom-containing components, thereby removing the gum and / or gum precursors from the pyrolysis oil and producing a purified pyrolysis oil. The purified pyrolysis oil can then be cracked to produce chemicals including olefins and aromatics.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 039,868, filed June 16, 2020, which is incorporated herein by reference in its entirety. Technical Field

[0003] This invention generally relates to systems and methods for processing pyrolysis oil. More specifically, this invention relates to systems and methods for pretreating pyrolysis oil to produce more stable pyrolysis oil products and / or more desirable pyrolysis oil feedstocks for cracking. Background Technology

[0004] Plastics are ubiquitous in industrial and household applications. With tons of plastic produced daily, the extremely long natural decomposition process of waste plastics has created serious environmental challenges. Therefore, various methods for reusing and / or recycling plastics have been explored over the past few decades.

[0005] Pyrolysis of blended plastics is a process that involves breaking down plastics at high temperatures to produce pyrolysis oil. This oil can be used directly as a liquid fuel or further processed to produce high-value chemicals. However, pyrolysis oil produced from blended plastics typically contains a high concentration of highly reactive chemicals, leading to rapid aging and the formation of gums during transportation and further processing. Therefore, scaling of the containers and / or chemical processing units that handle and / or process it is quite common for pyrolysis oil to form in the presence of trace amounts of oxygen.

[0006] In the context of this invention, at least twenty embodiments are now described. Embodiment 1 is a method for treating pyrolysis oil. The method includes the steps of: treating the pyrolysis oil with an adsorbent to remove gums and / or gum precursors from the pyrolysis oil to produce purified pyrolysis oil; and cracking the purified pyrolysis oil under reaction conditions sufficient to produce olefins and aromatic compounds. Embodiment 2 is the method of Embodiment 1, wherein the treatment step is further configured to increase the stability of the pyrolysis oil. Embodiment 3 is the method of any one of Embodiments 1 and 2, wherein the treatment step includes passing the pyrolysis oil through an adsorbent under treatment conditions sufficient to remove at least some, or one or more, of the following substances from the pyrolysis oil: (a) oxygen-containing compounds, (b) nitrogen-containing compounds, (c) chlorine-containing compounds, (d) polynuclear aromatic compounds and heavy tails (C 20(e) silicon-containing compounds, and (f) heavy metals. Embodiment 4 is the method of Embodiment 3, wherein the adsorbent is contained in a protective bed, purification column, stirred tank, fluidized bed, or a combination thereof. Embodiment 5 is the method of any one of Embodiments 3 and 4, wherein the adsorbent contains activated carbon (carbon), molecular sieve, bleached clay, silica hydrogel, ion exchange resin, cured eggshell powder, or a combination thereof. Embodiment 6 is the method of Embodiment 5, wherein the molecular sieve is configured to reduce the color of the pyrolysis oil, reduce total organic nitrogen, reduce the density of the pyrolysis oil, reduce the concentration of chlorinated compounds in the pyrolysis oil, reduce oxygenated compounds in the pyrolysis oil, minimize corrosion and / or scaling on downstream equipment, or a combination thereof. Embodiment 7 is the method of any one of Embodiments 5 and 6, wherein the molecular sieve contains K... 12 [(AlO2) 12 (SiO2) 12 ]·nH2O、Na 12 [(AlO2) 12 (SiO2) 12 ]·nH2O、Ca 4,5 [(AlO2) 12 (SiO2) 12 ]·nH2O、Na 86 [(AlO2) 86 (SiO2) 106 ·nH2O or a combination thereof. Embodiment 8 is the method of any one of embodiments 5 to 7, wherein the pore size of the molecular sieve is 3 to Implementation scheme 9 is the method of any one of implementation schemes 5 to 8, wherein the surface area of ​​the adsorbent is between 10 and 8000 m². 2Within the range of / g. Embodiment 10 is the method of any one of Embodiments 3 to 9, wherein the oxygen- and / or nitrogen-containing compounds include aliphatic acids, aromatic acids, nitriles, amines, aldehydes, aliphatic / cyclic ketones, cyclic amides, aliphatic / aromatic alcohols, glycols, esters, ethers, aliphatic / cyclic chlorides, furans, indoles, quinolines, phenolic compounds, indole compounds, acidic compounds, alcohols, amines, or combinations thereof. Embodiment 11 is the method of Embodiment 10, wherein the oxygen- and / or nitrogen-containing compounds include 2-heptadecanoone, 2-pentanone, caprolactam, 3-heptanol (methyl(iso2)), octadecanonitrile, oleananitrile, cyclopentanone, tridecanenitrile, heptanoic acid, doedecanophenone, 2-cyclopentenol, 1-butanol, benzoic acid, hexanonitrile, tridecanenitrile, 2-hydroxy-3-methyl-2-cyclopenten-1-one, C5-substituted (iso2)phenol, 3-ethyl-2-hydroxy-2-cyclopenten-1-one, or combinations thereof. Embodiment 12 is the method of any one of Embodiments 1 to 11, wherein the treatment conditions in the treatment step include a treatment temperature of 10 to 100°C. Embodiment 13 is the method of any one of Embodiments 1 to 12, wherein the treatment conditions in the treatment step include a treatment pressure of 0.1 to 10 bar. Embodiment 14 is the method of any one of Embodiments 1 to 13, wherein the adsorbent has substantially no effect or no effect on the hydrocarbon cracking value of the pyrolysis oil. Embodiment 15 is the method of any one of Embodiments 1 to 14, wherein the cracking includes steam cracking. Embodiment 16 is the method of Embodiment 15, wherein the steam cracking is carried out at a cracking temperature of 750 to 900°C. Embodiment 17 is the method of any one of Embodiments 15 and 16, wherein the steam cracking is carried out at a residence time of 1 to 4000 ms. Embodiment 18 is the method of any one of Embodiments 1 to 17, further comprising the steps of regenerating the adsorbent by thermal regeneration, thermal and vacuum regeneration, rinsing with a strong acid or strong alkali solution, solvent rinsing of the adsorbent, or a combination thereof. Embodiment 19 is the method of any one of Embodiments 1 to 18, further comprising removing the adsorbent from the purified pyrolysis oil by sedimentation, filtration, cyclone separation, or a combination thereof.

[0007] Implementation Scheme 20 is a method for treating pyrolysis oil. The method includes the steps of: treating the pyrolysis oil with one or more non-silica-based adsorbents to remove gums and / or gum precursors from the pyrolysis oil to produce purified pyrolysis oil; and using the purified pyrolysis oil as a liquid fuel.

[0008] In summary, although systems and methods exist for handling or storing pyrolysis oils derived from mixed plastics, improvements are needed in the art due to at least the aforementioned drawbacks of conventional systems and methods. Summary of the Invention

[0009] Solutions have been found to at least some of the aforementioned problems related to systems and methods for treating pyrolysis oil derived from plastics. The solution lies in a method for treating pyrolysis oil, comprising treating the oil with an adsorbent to (1) remove gums and / or gum precursors from the oil and / or (2) increase the stability of the oil, thereby reducing scaling and corrosivity of the purified oil. Furthermore, after the treatment step, the purified oil can be cracked to produce high-value products including olefins and aromatic compounds (e.g., BTX), increasing the value of the oil. Additionally, the oil can be obtained from mixed plastics, thereby reducing plastic pollution. The adsorbent can include materials with high surface areas (e.g., molecular sieves and activated carbon) or specific active targets for acidic or basic contaminants (e.g., ion exchange resins), which can significantly improve the adsorption efficiency for removing gum precursors and / or oxidants. Therefore, the disclosed method offers technical advantages over conventional methods for treating pyrolysis oil.

[0010] Embodiments of the present invention include a method for processing pyrolysis oil. The method includes treating the pyrolysis oil with an adsorbent to remove gums and / or gum precursors from the pyrolysis oil to produce purified pyrolysis oil. The method further includes cracking the purified pyrolysis oil under reaction conditions sufficient to produce olefins and aromatic compounds.

[0011] Embodiments of the present invention include a method for treating pyrolysis oil. The method comprises passing the pyrolysis oil through an adsorbent under treatment conditions sufficient to remove at least some, or one or more, of the following substances from the pyrolysis oil, and producing purified pyrolysis oil: (a) oxygen-containing compounds, (b) nitrogen-containing compounds, (c) chlorine-containing compounds, (d) polynuclear aromatic compounds, and heavy tail fractions (C... 20 (e) silicon-containing compounds, and (f) heavy metals. The method involves cracking purified pyrolysis oil under reaction conditions sufficient to produce olefins and aromatic compounds.

[0012] Embodiments of the present invention include a method for processing pyrolysis oil. The method comprises passing the pyrolysis oil through a protective bed containing an adsorbent, a purification column, a fluidized bed, and / or a stirred tank under treatment conditions sufficient to remove at least some, or one or more, of the following substances from the pyrolysis oil, and producing purified pyrolysis oil: (a) oxygen-containing compounds, (b) nitrogen-containing compounds, (c) chlorine-containing compounds, (d) polynuclear aromatic compounds, and heavy tail fractions (C... 20 (e) silicon-containing compounds, and (f) heavy metals. The method involves steam cracking to purify pyrolysis oil under reaction conditions sufficient to produce olefins and aromatic compounds.

[0013] Embodiments of the present invention include a method for treating pyrolysis oil. The method includes treating the pyrolysis oil with one or more non-silica-based adsorbents to remove colloids and / or colloid precursors from the pyrolysis oil to produce purified pyrolysis oil. The method also includes using the purified pyrolysis oil as a liquid fuel.

[0014] The following includes definitions of various terms and phrases used throughout this application.

[0015] The terms “about” or “approximately” are defined as close to, as understood by those skilled in the art. In one non-limiting embodiment, the term is defined as within 10%, preferably within 5%, more preferably within 1%, and most preferably within 0.5%.

[0016] The terms "wt%", "vol%", or "mol.%" refer to the weight percentage, volume percentage, or mole percentage of the component based on the total weight, total volume, or total number of moles of the material comprising the component. In a non-limiting example, 10 moles of the component in 100 moles of material constitutes 10 mol.% of the component.

[0017] The term “substantially” and its variations are defined as including the range within 10%, within 5%, within 1%, or within 0.5%.

[0018] The terms “suppress” or “reduce” or “prevent” or “avoid” or any variations thereof, when used in the claims and / or specification, include any measurable amount of reduction or complete suppression to achieve the desired result.

[0019] The term “effective” as used in the specification and / or claims means sufficient to achieve the desired, anticipated, or intended result.

[0020] The term "colloid" as used in the specification and / or claims refers to the solid and / or creamy and / or semi-solid portions that are gradually removed from liquid pyrolysis oil. In embodiments of the invention, "colloid" may include components with an average molecular weight of 400 Daltons that are soluble or exfoliated from solutions and / or liquids. Many cracked gasolines, especially those that are unrefined, may contain viscous, resinous substances that deposit under certain conditions and can include colloidal substances. For example, when left for extended periods under dark or diffused light conditions, a semi-fluid substance called "colloid" typically accumulates gradually at the bottom of the oil as a brown, viscous substance. Another example of "colloid" may include a dark brown, hard, resinous residue that can be obtained by evaporating liquid products comprising cracked gasoline and / or pyrolysis oil in a copper pan.

[0021] The term "stability" as used in the specification and / or claims refers to the fact that the pyrolysis oil composition is not altered by chemical reactions over time. In embodiments of the invention, "stability" may refer to the limited or non-existent reactivity of the pyrolysis oil (treated with the adsorbent) due to the removal / capture of reactive substances by the adsorbent. Therefore, there is essentially no or no further formation of colloids or any other color change, and the properties remain unchanged for a considerable period after purification.

[0022] When used in the claims or description with the terms “comprising,” “including,” “containing,” or “having,” the use of the words “a” or “an” can mean “one,” but it also has the meanings of “one or more,” “at least one,” and “one or more.”

[0023] The terms “comprising” (and any form of inclusion, such as “comprise” and “comprises”), “having” (and any form of having, such as “have” and “has”), “including” (and any form of inclusion, 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, unlisted elements or method steps.

[0024] The method of the present invention may "comprise" specific ingredients, components, compositions, etc. disclosed throughout the specification, "consistently constitute" or "composed of".

[0025] As used in the specification and / or claims, the term "major" means any one of 50 wt.%, 50 mol.%, and 50 vol.%. For example, "major" can include all values ​​and ranges from 50.1 wt.% to 100 wt.%, from 50.1 mol.% to 100 mol.%, or from 50.1 vol.% to 100 vol.%.

[0026] Other objects, features, and advantages of the present invention will become apparent from the following drawings, detailed description, and embodiments. However, it should be understood that while indicating specific embodiments of the invention, the drawings, detailed description, and embodiments are given by way of illustration only and are not intended to be limiting. Furthermore, changes and modifications within the spirit and scope of the invention are expected to become apparent to those skilled in the art from this detailed description. In further embodiments, features from a specific embodiment may be combined with features from other embodiments. For example, a feature from one embodiment may be combined with a feature from any other embodiment. In further embodiments, additional features may be added to the specific embodiments described herein. Attached Figure Description

[0027] For a more complete understanding, please refer to the following description in conjunction with the accompanying drawings, in which:

[0028] Figure 1 A schematic diagram of a system for processing pyrolysis oil according to an embodiment of the present invention is shown;

[0029] Figure 2 A schematic flowchart of a method for processing pyrolysis oil according to an embodiment of the present invention is shown;

[0030] Figure 3A Photographs of pyrolysis oils treated with different materials and / or methods are shown (from left to right: molecular sieve, air purging, blank, and blank);

[0031] Figure 3B It shows the corresponding Figure 3A Gray-scale analysis of gum formation in pyrolysis oil samples;

[0032] Figure 3C The formation of colloids under different amounts of molecular sieves is shown;

[0033] Figure 3D It shows that for Figure 3C For each sample, the processed pyrolysis oil showed colloidal deposits and color at the bottom;

[0034] Figure 4A and 4B This shows a photograph of gum formation in pyrolysis oil using different types of molecular sieves on day 0. Figure 4A The small bottle was shown standing upright. Figure 4B (The small bottle is shown with its bottom facing up);

[0035] Figure 4C and 4D This shows a photograph of gum formation in pyrolysis oil using different types of molecular sieves on day 30. Figure 4C The small bottle was shown standing upright. Figure 4D(The small bottle is shown with its bottom facing up);

[0036] Figure 5 A comparison of colloidal formation and color changes in pyrolysis oil samples treated with molecular sieves (middle) and activated carbon (right) is shown;

[0037] Figure 6A Photographs showing the colors of pyrolysis oils treated with different molecular sieves are provided.

[0038] Figure 6B It shows Figure 6A The changes in RGB% in the sample shown;

[0039] Figure 7A The color changes of pyrolysis oil treated with different amounts of molecular sieves are shown.

[0040] Figure 7B The color changes of pyrolysis oil treated with different amounts of activated carbon are shown.

[0041] Figure 8A The grayscale analysis shows the changes in the darkness of pyrolysis oil treated with different amounts of molecular sieves.

[0042] Figure 8B The grayscale analysis shows the changes in the darkness of pyrolysis oil treated with different amounts of activated carbon.

[0043] Figure 8C It shows the corresponding Figure 8A RGB% results of the sample;

[0044] Figure 8D It shows the corresponding Figure 8B RGB% results of the sample;

[0045] Figure 9 The changes in total organic nitrogen (TON) in pyrolysis oil treated with molecular sieves and activated carbon are shown.

[0046] Figure 10 The changes in density in pyrolysis oil treated with molecular sieves and activated carbon are shown.

[0047] Figure 11 The changes in hydrocarbon composition (carbon number) of untreated and pyrolysis oils treated with molecular sieves and activated carbon are shown; and

[0048] Figure 12 The changes in selected chlorinated species in pyrolysis oil treated with molecular sieves and activated carbon are shown. Detailed Implementation

[0049] Currently, pyrolysis oils, especially those derived from plastic pyrolysis, have high gum or gum precursor content, leading to high gum formation, low stability, and high acidity. Therefore, storing, transporting, and / or handling pyrolysis oils in chemical plants is very challenging, often resulting in their direct combustion as fuel. This invention provides solutions to at least some of these problems. The premise of this solution is a method for treating pyrolysis oils. This method involves first treating the pyrolysis oil with an adsorbent to remove gums and / or gum precursors, thereby reducing the corrosiveness and scaling risk of the pyrolysis oil. Furthermore, by removing gum precursors, the stability of the pyrolysis oil can be significantly improved for storage, transportation, and further processing. Moreover, the purified pyrolysis oil produced by the treatment step can be used in cracking processes to produce high-value chemicals such as olefins, including light olefins (C2 to C4 olefins), C5 olefins, and BTX (benzene, toluene, and xylene). These and other non-limiting aspects of the invention are discussed in further detail in the following sections.

[0050] A. Systems for processing pyrolysis oil

[0051] In embodiments of the invention, the disclosed system may include a purification unit and a cracking unit. According to embodiments of the invention, the system is configured to facilitate the production of high-value chemicals from pyrolysis oil while reducing scaling and corrosion in the cracking unit. Reference Figure 1 A schematic diagram of a system 100 for processing pyrolysis oil is shown.

[0052] According to an embodiment of the invention, system 100 includes a purification unit 101 configured to (1) remove gums and / or gum precursors from the pyrolysis oil of pyrolysis oil stream 11, and / or (2) increase the stability of the pyrolysis oil to produce a purified pyrolysis oil stream 12 containing purified pyrolysis oil. The pyrolysis oil stream 11 may include pyrolysis oil obtained by pyrolysis of mixed plastics. In an embodiment of the invention, purification unit 101 may include an adsorbent. The adsorbent includes a surface region configured to capture, adsorb, and / or remove at least some, or one or more, of the following substances from the pyrolysis oil of pyrolysis oil stream 11: (a) oxygen-containing compounds, (b) nitrogen-containing compounds, (c) chlorine-containing compounds, (d) polynuclear aromatic compounds, and heavy tail fractions (C 20 (e) silicon-containing compounds, and (f) heavy metals, thereby removing gums and / or gum precursors from pyrolysis oil and increasing the stability of the pyrolysis oil. In embodiments of the invention, the adsorbent is configured to further remove other heteroatom-containing compounds that are not gums or gum precursors. In embodiments of the invention, the adsorbent is configured to further remove other oxygen-containing compounds, nitrogen-containing compounds, and chlorine-containing compounds that are not gums or gum precursors.

[0053] In embodiments of the present invention, oxygen- and / or nitrogen-containing compounds may include aliphatic acids, aromatic acids, nitriles, amines, aldehydes, aliphatic / cyclic ketones, cyclic amides, aliphatic / aromatic alcohols, glycols, esters, ethers, aliphatic / cyclic chlorides, furans, indoles, quinolines, phenolic compounds, indole compounds, acidic compounds, alcohols, amines, or combinations thereof. Oxygen- and / or nitrogen-containing compounds may include 2-heptadecanoone, 2-pentanone, caprolactam, 3-heptanol, methyl(iso2) , octadeconitrile, oleanolic acid, cyclopentanone, tridecanonitrile, heptanoic acid, doedecanophenone, 2-cyclopentenol, 1-butanol, benzoic acid, hexanonitrile, tridecanonitrile, 2-hydroxy-3-methyl-2-cyclopenten-1-one, C5-substituted (iso2) phenol, 3-ethyl-2-hydroxy-2-cyclopenten-1-one, or combinations thereof.

[0054] In embodiments of the invention, exemplary adsorbents for purification unit 101 may include activated carbon (carbon), molecular sieves, bleached clay, silica hydrogel, ion exchange resin, cured eggshell powder, and combinations thereof. Purification unit 101 may include a combination of adsorbents, wherein the type of adsorbent is selected based on the type and concentration of compounds to be removed from the pyrolysis oil. The surface area of ​​the adsorbent can range from 10 to 8000 m². 2 Within the range of / g, and all ranges and values ​​within it, including 10 to 50m 2 / g, 50 to 100m 2 / g, 100 to 400m 2 / g, 400 to 700m 2 / g, 700 to 1000m 2 / g, 1000 to 2000m 2 / g, 2000 to 4000m 2 / g, 4000 to 6000m 2 / g to 000 to 8000m 2 / g range. According to embodiments of the invention, the adsorbent of the purification unit comprises a molecular sieve, and the molecular sieve is configured to reduce the color of the pyrolysis oil, reduce the total organic nitrogen in the pyrolysis oil, reduce the density of the pyrolysis oil, reduce the concentration of chlorine-containing compounds in the pyrolysis oil, reduce the concentration of oxygen-containing compounds in the pyrolysis oil, minimize corrosion and / or scaling on downstream equipment, or a combination thereof. In embodiments of the invention, the molecular sieve comprises K 12 [(AlO2) 12 (SiO2) 12 ]·nH2O、Na 12 [(AlO2) 12(SiO2) 12 ]·nH2O、Ca 4,5 [(AlO2) 12 (SiO2) 12 ]·nH2O、Na 86 [(AlO2) 86 (SiO2) 106 ·nH₂O or combinations thereof. The pore size of the molecular sieve can be 3 to and all ranges and values ​​in between, including 3 to 4 to 5 to 6 to 7 to 8 to and 9 to The range of molecular sieves is defined. Molecular sieves can be in the form of particles, flakes, beads, powders, or combinations thereof.

[0055] In embodiments of the present invention, the adsorbent comprises activated carbon (carbon). The pore size of the activated carbon can be 1 to... Within a certain range. The surface area of ​​activated carbon can range from 10 to 8000 m². 2 / g. In embodiments of the present invention, purification unit 101 may include a guard bed, a purification column, a fluidized bed, a stirred tank, or a combination thereof. The adsorbent in purification unit 101 may form a fixed bed and / or a fluidized bed, or be dispersed in a stirred tank.

[0056] According to an embodiment of the invention, the outlet of purification unit 101 is in fluid communication with cracking unit 102, such that purified pyrolysis oil stream 12 flows from purification unit 101 to cracking unit 102. In an embodiment of the invention, cracking unit 102 may be configured to crack the purified pyrolysis oil from purified pyrolysis oil stream 12 to produce product stream 13 containing olefins and aromatic compounds. In an embodiment of the invention, cracking unit 102 may include a steam cracker, a hydrocracker, and / or a fluid catalytic cracker. In an embodiment of the invention, cracking unit 102 may include a hydrotreating unit installed upstream of the steam cracker, hydrocracker, and / or fluid catalytic cracker, the hydrotreating unit being configured to hydrotreat the purified pyrolysis oil before it flows into the steam cracker, hydrocracker, and / or fluid catalytic cracker. Product stream 13 may include light olefins and BTX (benzene, toluene, xylene).

[0057] In embodiments of the invention, purification unit 101 includes an adsorbent in powder form, and system 100 may include a separation unit installed between purification unit 101 and cracking unit 102. The separation unit may be configured to separate the adsorbent from the purified pyrolysis oil stream 12 before it flows into cracking unit 102. In embodiments of the invention, the separation unit may include a settling unit, a membrane, a filtration unit, a cyclone separator, or a combination thereof.

[0058] According to an embodiment of the invention, system 100 may include an adsorbent regeneration unit configured to regenerate the adsorbent (saturated or partially saturated) from purification unit 101 to remove colloids and / or colloid precursors and produce regenerated adsorbent. As an alternative to or supplement to the adsorbent regeneration unit, when purification unit 101 is not used to process the pyrolysis oil stream 11, the adsorbent (saturated or partially saturated) may be regenerated in purification unit 101. In embodiments of the invention, at least a portion of the saturated or partially saturated adsorbent in purification unit 101 may be discarded without regeneration.

[0059] B. Methods for treating pyrolysis oil

[0060] A method for treating pyrolysis oil has been discovered. Compared to conventional methods, this method can reduce scaling and / or corrosion caused by pyrolysis oil during storage and / or chemical production. Figure 2 As shown, an embodiment of the present invention includes a method 200 for processing pyrolysis oil. Method 200 can be performed as follows: Figure 1 The system 100 shown and described above is implemented. According to an embodiment of the invention, as shown in block 201, method 200 includes treating the pyrolysis oil of pyrolysis oil stream 11 with the adsorbent of purification unit 101 to remove gums and / or gum precursors from the pyrolysis oil and / or increase the stability of the pyrolysis oil to produce a purified pyrolysis oil stream 12 containing purified pyrolysis oil. In an embodiment of the invention, the treatment in block 201 is configured to further remove other heteroatom-containing compounds that are not gums or gum precursors. In an embodiment of the invention, the treatment in block 201 is configured to further remove other oxygen-containing compounds, nitrogen-containing compounds, and chlorine-containing compounds that are not gums or gum precursors. In an embodiment of the invention, the pyrolysis oil comprises pyrolysis oil derived from the pyrolysis of mixed plastics, and the boiling point range of the pyrolysis oil is 100 to 600°C. The boiling profile range of the pyrolysis oil derived from the pyrolysis of mixed plastics is 20 to 600°C.

[0061] In an embodiment of the invention, the treatment of block 201 may include treating the pyrolysis oil by passing it through the adsorbent of purification unit 101 under treatment conditions sufficient to remove at least some, or one or more, of the following substances from the pyrolysis oil: (a) oxygen-containing compounds, (b) nitrogen-containing compounds, (c) chlorine-containing compounds, (d) polynuclear aromatic compounds and heavy tail fractions (C 20 (a) oxygen-containing compounds, (b) nitrogen-containing compounds, (c) chlorine-containing compounds, (d) polynuclear aromatic compounds and heavy tail fractions (C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C1 ... 20 (a) silicon-containing compounds, and (f) heavy metals. In embodiments of the invention, the processing conditions of the processing step in block 201 include temperatures from 10 to 100°C, and all ranges and values ​​therebetween, including the ranges of 10 to 20°C, 20 to 30°C, 30 to 40°C, 40 to 50°C, 50 to 60°C, 60 to 70°C, 70 to 80°C, 80 to 90°C, and 90 to 100°C. The processing conditions of the processing step in block 201 may further include pressures from 0.1 to 10 bar. In embodiments of the invention, the adsorbent of purification unit 101 may include activated carbon (carbon), molecular sieves, bleached clay, silica hydrogel, ion exchange resin, cured eggshell powder, and combinations thereof. Purification unit 101 may include a combination of adsorbents, wherein the type of adsorbent is selected based on the type and concentration of compounds to be removed from the pyrolysis oil. In an embodiment of the invention, the adsorbent in purification unit 101 is disposed in a fixed bed, and the processing conditions of the processing step in block 201 may further include 0.1 to 10 hours. -1 And all ranges and values ​​of the time-space velocity in between, including 0.1 to 0.5 hr. -1 0.5 to 1 hour -1 1 to 2 hours -1 2 to 4 hours -1 4 to 6 hours -1 6 to 8 hours -1 and 8 to 10 hours -1The range of values ​​is specified. In embodiments of the invention, the adsorbent of purification unit 101 is dispersed in a stirred tank, and the processing conditions of the processing step in block 201 may further include mixing times ranging from 1 minute to 10 hours and all values ​​therebetween, including 1 to 10 minutes, 10 to 30 minutes, 30 minutes to 1 hour, 1 to 2 hours, 2 to 3 hours, 3 to 4 hours, 4 to 5 hours, 5 to 6 hours, 6 to 7 hours, 7 to 8 hours, 8 to 9 hours, and 9 to 10 hours. In embodiments of the invention, pyrolysis oil generated from plastic pyrolysis can flow directly through the adsorbent without other pretreatment (e.g., alkaline washing). In embodiments of the invention, the adsorbent used in purification unit 101 in block 201 may be free of any added chemicals.

[0062] In an embodiment of the invention, the treatment in block 201 is further configured to reduce the color of the pyrolysis oil, reduce total organic nitrogen, reduce the density of the pyrolysis oil, reduce the concentration of chlorine-containing compounds in the pyrolysis oil, reduce oxygen-containing compounds in the pyrolysis oil, minimize corrosion and / or scaling on downstream equipment, or a combination thereof.

[0063] In an embodiment of the present invention, the purified pyrolysis oil stream 12 comprises 0.01 to 2.5 wt.% oxygen-containing compounds, 0.01 to 0.1 wt.% nitrogen-containing compounds, 0.0001 to 0.01 wt.% chlorine-containing compounds, 0.5 to 10 wt.% polynuclear aromatic compounds, and heavy tail fraction (C 20 +), 0.0001 to 0.01 wt.% silicon-containing compounds, and / or 0.0001 to 0.01 wt.% heavy metals.

[0064] According to an embodiment of the invention, as shown in block 202, method 200 includes, optionally, removing the adsorbent from the purified pyrolysis oil stream 12 in a separation unit when purification unit 101 includes an adsorbent formed from powder. In an embodiment of the invention, the removal in block 202 includes settling the adsorbent from the purified pyrolysis oil stream 12, filtering the purified pyrolysis oil stream 12, and / or treating the purified pyrolysis oil stream 12 in a cyclone separation unit and / or a membrane unit.

[0065] According to an embodiment of the invention, as shown in block 203, method 200 includes cracking the purified pyrolysis oil of purified pyrolysis oil stream 12 in cracking unit 102 under reaction conditions sufficient to produce olefins and aromatic compounds in product stream 13. In an embodiment of the invention, the reaction conditions in block 203 include a reaction temperature of 750 to 900°C and a residence time of 1 to 4000 ms. In an embodiment of the invention, the cracking in block 203 includes a steam cracking process, a fluidized catalytic cracking process, a hydrocracking process, and / or a hydrotreating process. In an embodiment of the invention, product stream 13 contains 10 to 50 wt.% olefins.

[0066] According to an embodiment of the invention, as shown in block 204, method 200 includes regenerating a partially saturated or saturated adsorbent from purification unit 101 to produce regenerated adsorbent. In an embodiment of the invention, the regeneration in block 204 may include burning the saturated or saturated adsorbent (thermal regeneration), vacuum and thermal regeneration, rinsing with a strong acid or strong base solution, and / or rinsing with a polar organic solvent (e.g., tetrahydrofuran (THF)). In an embodiment of the invention, at least some of the saturated or saturated adsorbent may be discarded without regeneration.

[0067] Although it has been referenced Figure 2 The boxes described embodiments of the present invention, but it should be understood that the operation of the present invention is not limited to these. Figure 2 The specific boxes and / or the order of specific boxes shown. Therefore, embodiments of the present invention can be implemented with... Figure 2 Different sequences of boxes are used to provide the functionality described in this article.

[0068] The systems and methods described herein may also include various devices not shown but known to those skilled in the art of chemical processing. For example, devices such as controllers, pipes, computers, valves, pumps, heaters, thermocouples, pressure indicators, mixers, heat exchangers, etc., may not be shown.

[0069] As part of this disclosure, specific embodiments are included below. These embodiments are for illustrative purposes only and are not intended to limit the invention. Those skilled in the art will readily recognize that parameters can be modified or improved to produce substantially the same results.

[0070] Example 1

[0071] (Treatment of pyrolysis oil with adsorbent)

[0072] Approximately 0.1 to 2 g of various adsorbent materials, including molecular sieves and activated carbon, were added to 10 mL of pyrolysis oil in a 20 mL vial. The mixture was stored for several days and colloidal deposits were observed.

[0073] Pyrolysis oil was treated with molecular sieves and air purging (He, N2, air), and then compared with an untreated control. Figure 3A (Visually estimated) and Figure 3B (corresponding to) Figure 3A The results (grayscale values ​​of each vial) clearly demonstrate that the molecular sieve can prevent the formation of colloids. The quantitative grayscale values ​​for colloid formation ( Figure 3B This indicates that purging the pyrolysis oil with air for one minute has no significant effect on the formation of gums.

[0074] exist Figures 3A-3DIn the study, compared with the blank (control), air purging did not significantly reduce gum formation. A quantity-dependent effect of molecular sieves on gum formation in pyrolysis oil was observed, confirming a positive correlation between the amount of molecular sieves (from left to right: 0.1g, 0.5g, 1g, 1.5g, 2g, 0g) and gum formation. Figure 3C and 3D ).

[0075] Will have different compositions (K) 12 [(AlO2) 12 (SiO2) 12 ]·nH2O、Na 12 [(AlO2) 12 (SiO2) 12 ]·nH2O、Ca 4,5 [(AlO2) 12 (SiO2) 12 ]\·nH2O、Na 86 [(AlO2) 86 (SiO2) 106 Several commercially available molecular sieves with nH2O and porosity (3-10 Å) were tested with N2 purging and blank pyrolysis oil samples, such as... Figures 4A-4D As shown. 3A corresponds to K. 12 [(AlO2) 12 (SiO2) 12 ]·nH2O,4A corresponds to Na with different porosities and forms (beads / discs). 12 [(AlO2) 12 (SiO2) 12 ]·nH2O,5A corresponds to Ca 4,5 [(AlO2) 12 (SiO2) 12 ]\·nH2O,13X corresponds to Na 86 [(AlO2) 86 (SiO2) 106 ]·nH2O.

[0076] The results clearly demonstrate that most of the tested molecular sieves are effective in reducing colloidal formation. Similar to molecular sieves, activated carbon also showed evidence of reduced colloidal formation, such as... Figure 5 As shown in the figure. Furthermore, concentration-dependent experiments indicate that activated carbon is significantly more effective at preventing colloid formation.

[0077] Example 2

[0078] (Treatment of pyrolysis oil with adsorbent)

[0079] Approximately 0.1 to 2 g of various adsorbent materials, including molecular sieves and activated carbon, are added to 10 mL of pyrolysis oil in a 20 mL vial. The mixture is stored for a specific period. The color change, total organic nitrogen, and oxygen-containing compound changes of the sample are tested. Color changes are examined visually and by grayscale and RGB% analysis. Density is measured by weight relative to a specific volume. Chloride is detected and quantified using a GC×GC-HRMS system. Total organic nitrogen content is measured using an isocratic GC-NCD system. Oxygen-containing compound measurements are evaluated using a comprehensive GC×GC-HRMS system. Oxygen-containing compounds in the pyrolysis oil are measured by direct injection of the pyrolysis oil, while components captured by the molecular sieve / activated carbon are measured by extraction with tetrahydrofuran followed by injection into the GC×GC system.

[0080] Experiments on different types of molecular sieves have shown varying degrees of effectiveness in reducing the darkness of pyrolysis oil. Figures 6A-6B Analysis based on RGB% () Figure 6B The results showed that primarily the red (positive) and blue (negative) components were affected by the reduction of pyrolysis oil color. Further dose-dependent (0.1-2g) studies indicated that both molecular sieves and activated carbon were highly positively correlated in reducing pyrolysis oil color. Figure 7A (Molecular sieve) and 7B (activated carbon (carbon)) are shown.

[0081] Quantitative analysis of the grayscale value of the amount-dependent effect of pyrolysis oil color further confirms this point. Figures 8A-8B In comparison, activated carbon was more effective at reducing the dark color of pyrolysis oil. The results of the darkening reduction were based on a quantity-dependent RGB% ratio. Figure 8C-8D This study confirmed that for molecular sieves, the red (positive) and blue (negative) components were affected by the dilution of the pyrolysis oil color. In contrast, for activated carbon, the green component showed a positive correlation, while the changes in the red and blue components showed no significant correlation.

[0082] These results further suggest that microporous molecular sieves and mesoporous activated charcoal adsorb different kinds of compounds with different affinities.

[0083] Reduction in total organic nitrogen: like Figure 9 As shown, the total organic nitrogen (TON) content measured by the isocratic GC-NCD system confirmed that both molecular sieve-treated and activated carbon-treated pyrolysis oils exhibited significant reductions in TON compared to untreated blank pyrolysis oil. Activated carbon showed better TON reduction compared to molecular sieves. This indicates a strong correlation between chromatographs and nitrogen-containing compounds, which are largely captured by both molecular sieves and activated carbon.

[0084] Density decreases: like Figure 10As shown, dose-dependent treatment with both molecular sieves and activated carbon resulted in a decrease in the density of the treated pyrolysis oil. Compared to conventional concentrates, the maximum amounts of molecular sieves and activated carbon produced density reductions of approximately 15% and 30%, respectively.

[0085] Detailed hydrocarbon type analysis (PINA) showed that both activated carbon and molecular sieves reduced heavier hydrocarbons, with activated carbon treatment resulting in a significantly greater reduction. Figure 11 The reduction of these heavy hydrocarbons helps to lower the density of the processed pyrolysis oil.

[0086] The reduction of chlorine-containing compounds: Speciation analysis of chlorine-containing compounds clearly shows that treatment with molecular sieves and activated carbon both lead to a reduction in chlorine-containing compounds. For example... Figure 12 Several representative chlorinated species in the sample were shown to have been significantly reduced after treatment with molecular sieves and activated carbon. This clearly demonstrates that these treatments have the potential to reduce the total chlorinated compounds in pyrolysis oil.

[0087] The reduction of oxygen-containing compounds: Comprehensive GC×GC-HRMS analysis showed that the amount of oxygen-containing compounds in pyrolysis oil treated with molecular sieves and activated carbon was significantly lower than that in the control compared to untreated pyrolysis oil. Further analysis clearly indicated that carboxylic acids, phenols, ketones, and aldehydes were the main contributors to the oxygen-containing compounds present in the pyrolysis oil, and these compounds were significantly eliminated from the treated pyrolysis oil. Although activated carbon removed a large amount of oxygen-containing compounds, some carboxylic acids remained in the treated pyrolysis oil. In contrast, compared to molecular sieve treatment, activated carbon-treated pyrolysis oil showed a significant reduction in di / polyaromatic compounds.

[0088] Further in-depth analysis of heteroatoms clearly shows that most unwanted heteroatoms are significantly reduced, by up to 30 times (activated carbon) or 140 times (molecular sieves), and even reduced to undetectable levels (see Tables 1, 2 and 3).

[0089] Table 1

[0090]

[0091] Table 2

[0092]

[0093]

[0094] Table 3

[0095]

[0096] Further analysis of the treated molecular sieves and activated carbon, through extraction with tetrahydrofuran of the captured and / or adsorbed components, revealed that the molecular sieves primarily captured oxygen-containing compounds and residual long-chain alkanes, while the activated carbon captured and / or adsorbed oxygen-containing compounds, di / polyaromatic compounds, and residual alkanes. This result confirms... Figure 8C and 8D The findings show the different RGB% values ​​of molecular sieves and activated carbon.

[0097] Although the embodiments and advantages of this application have been described in detail, it should be understood that various changes, substitutions, and modifications can be made herein without departing from the spirit and scope of the embodiments as defined by the appended claims. Furthermore, the scope of this application is not intended to be limited to the specific embodiments of the processes, machines, manufactures, compositions of matter, apparatuses, methods, and steps described in the specification. As will be readily understood by those skilled in the art from the foregoing disclosure, existing or future processes, machines, manufactures, compositions of matter, apparatuses, methods, or steps that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein can be utilized. Therefore, the appended claims are intended to include such processes, machines, manufactures, compositions of matter, apparatuses, methods, or steps within their scope.

Claims

1. A method for treating pyrolysis oil derived from plastics, the method comprising: Pyrolysis oil is treated with an adsorbent to remove colloids and / or colloid precursors to produce purified pyrolysis oil. and The pyrolysis oil is purified by cracking under reaction conditions sufficient to produce olefins and aromatic compounds. The adsorbent comprises 3A, 4A, 5A or 13X molecular sieves or combinations thereof, wherein the molecular sieve has a pore size of 3 to 10 Å.

2. The method of claim 1, wherein the processing step is further configured to increase the stability of the pyrolysis oil.

3. The method according to any one of claims 1 and 2, wherein the treatment step comprises passing the pyrolysis oil through an adsorbent under treatment conditions sufficient to reduce the amount of one or more of the following substances from the pyrolysis oil: (a) oxygen-containing compounds, (b) nitrogen-containing compounds, (c) chlorine-containing compounds, (d) polynuclear aromatic compounds and heavy tail fractions, (e) silicon-containing compounds, and (f) heavy metals.

4. The method according to claim 3, wherein the adsorbent is contained in a protective bed, a purification column, a stirred tank, a fluidized bed, or a combination thereof.

5. The method of claim 1, wherein the molecular sieve is configured to reduce the color of the pyrolysis oil, reduce total organic nitrogen, reduce the density of the pyrolysis oil, reduce the concentration of chlorine compounds in the pyrolysis oil, reduce oxygen compounds in the pyrolysis oil, minimize corrosion and / or scaling on downstream equipment, or a combination thereof.

6. The method according to claim 1, wherein the surface area of ​​the adsorbent is between 10 and 8000 m². 2 Within the range of / g.

7. The method according to claim 3, wherein the oxygen- and / or nitrogen-containing compounds include nitriles, amines, aldehydes, aliphatic ketones, cyclic ketones, cyclic amides, esters, ethers, furans, quinolines, indole compounds, acidic compounds, alcohols, or combinations thereof.

8. The method according to claim 7, wherein the oxygen- and / or nitrogen-containing compounds include 2-heptadecone, 2-pentanone, caprolactam, octadeconitrile, oleanolic acid, cyclopentanone, heptanoic acid, lauryl benzophenone, 2-cyclopentenol, 1-butanol, benzoic acid, hexanonitrile, tridecanonitrile, 2-hydroxy-3-methyl-2-cyclopenten-1-one, 2-hydroxy-3-ethyl-2-cyclopenten-1-one, or combinations thereof.

9. The method according to any one of claims 1 to 2, wherein the processing conditions in the processing step include a processing temperature of 10 to 100°C.

10. The method according to any one of claims 1 to 2, wherein the processing conditions in the processing step include a processing pressure of 0.1 to 10 bar.

11. The method according to any one of claims 1 to 2, wherein the adsorbent has no effect on the hydrocarbon cracking value of the pyrolysis oil.

12. The method according to any one of claims 1 to 2, wherein the cracking comprises steam cracking.

13. The method of claim 12, wherein the steam cracking is carried out at a cracking temperature of 750 to 900°C.

14. The method of claim 12, wherein the steam cracking is carried out at a residence time of 1 to 4000 ms.

15. The method according to any one of claims 1 to 2, further comprising the steps of regenerating the adsorbent by thermal regeneration, thermal and vacuum regeneration, rinsing with a strong acid or strong alkali solution, solvent rinsing of the adsorbent, or a combination thereof.

16. The method according to any one of claims 1 to 2, further comprising removing the adsorbent from the purified pyrolysis oil by sedimentation, filtration, cyclone separation or a combination thereof.

17. A method for treating pyrolysis oil derived from plastics, the method comprising: Pyrolysis oil is treated with one or more adsorbents to remove colloids and / or colloid precursors to produce purified pyrolysis oil; And using purified pyrolysis oil as liquid fuel, The one or more adsorbents mentioned herein include 3A, 4A, 5A or 13X molecular sieves or combinations thereof with a pore size of 3 to 10 Å.

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