Method for producing high-value-added chemicals using waste plastics

Abstract

The present disclosure relates to a method for producing high-value-added chemicals using waste plastics, the method comprising the steps of: a) pyrolyzing waste plastic feedstock to generate an oil-containing stream; b) reacting a part or all of the oil-containing stream in the presence of a catalyst in at least one circulating fluidized bed reactor; and c) separating and recovering high-value-added chemicals from the reaction product, wherein the oil-containing stream produced in step a) is fed into the reactor of step (b) without a process of removing olefins and non-hydrocarbon substances, and the catalyst contains phosphorus (P), has one or more metals selected from Cu, Ag, La, Ga, and Ni loaded thereto, and is pre-treated by pre-steaming.

Description

A method for manufacturing high value-added chemicals using waste plastics

[0001] The present disclosure relates to a method for producing high value-added chemicals from waste plastic.

[0002] High-value-added chemicals such as ethylene, propylene, C4 olefins, benzene, toluene, and xylene are widely used as raw materials for plastic manufacturing in the chemical industry. These chemicals are primarily produced through the pyrolysis of petroleum-derived naphtha. However, this process consumes significant energy due to the high-temperature reaction temperature exceeding 850°C and generates large amounts of greenhouse gases. Therefore, energy-efficient technologies are needed to produce high-value-added chemicals using sustainable materials such as waste plastics. Polyolefin plastics, such as polyethylene (PE) and polypropylene (PP), widely used in packaging materials, account for more than 60% of global waste plastic due to their short lifespans. Mechanical recycling of these waste plastics is difficult to widely apply due to impurities from other plastics (e.g., polyethylene terephthalate (PET), polystyrene (PS), and polyurethane (PU)), additives, and fillers. Furthermore, landfilling and incineration are unsuitable approaches due to their potential to cause environmental pollution. Therefore, to reduce the negative environmental impact of existing waste plastic disposal methods and transition to a circular economy with lower carbon emissions, the development of new energy-efficient processes to convert waste plastic into valuable, high-value chemicals is necessary.

[0003] In this context, a method is actively being developed to produce high-value-added chemicals by hydrogenating pyrolysis oil produced from the pyrolysis of waste plastics and then using it as a feedstock for conventional naphtha cracking processes (JP 6942178). In this process, waste plastics are degraded in the absence of oxygen, producing gases, liquid oils, and residues. Pyrolysis oil from waste plastics contains hydrocarbons with various structures, ranging from C5 to polymeric waxes. This composition is highly dependent on the degradation conditions, such as reactor type, reaction temperature, and heating rate, as well as the type of waste plastic. The resulting pyrolysis oil primarily contains olefins, paraffins, and aromatic compounds, with olefins being the dominant component. The resulting pyrolysis oil undergoes hydrogenation to remove impurities and contaminants and is then converted into high-value-added chemicals through conventional naphtha cracking processes. However, pyrolysis oil derived from waste plastics has different properties from petroleum-derived naphtha, making it difficult to directly use it as a feedstock for naphtha cracking processes.

[0004] First, there is the problem of hydrocarbon composition in pyrolysis oil. The carbon number of waste plastic pyrolysis oil is generally from C5 to C 44 It is composed of a wide range of carbon numbers, whereas naphtha is composed of carbon numbers from C5 to C9. Therefore, the fraction that can be processed in the existing naphtha cracking process is only less than 40% of the pyrolysis oil.

[0005] Second, during the pyrolysis of waste plastic, approximately 30-50% of the pyrolysis oil is olefin-containing. Because high olefin contents induce coke formation during the decomposition reaction, industry typically limits the olefin content in naphtha to a maximum of 1-2 wt%. To address this, hydrogenation is essential before pyrolysis oil is introduced into the naphtha cracking process.

[0006] Third, pyrolysis oil derived from waste plastic contains a large amount of heteroatom compounds (N, S, halogen, O, P, etc.) and metals (Al, Sb, Ba, Ca, Cr, Cu, Fe, K, Na, Pb, Si, Ti, Zn, As, Hg, Ni, V, etc.) that are not contained in conventional naphtha or are relatively low in content. In particular, chlorine compounds generated by PVC or salt in waste plastic require thorough management as they can cause sudden accidents due to stress corrosion cracking within the facility. To solve this problem, it is essential to remove impurities through a hydrogenation reaction before feeding pyrolysis oil into the naphtha cracking process.

[0007] However, this process of removing olefins and impurities through hydrogenation requires a separate reactor and consumes large amounts of expensive hydrogen, which can negatively impact economic efficiency. Therefore, a new method is needed to utilize the entire waste plastic pyrolysis oil, produce high-value-added chemicals from waste plastics without using hydrogen, and with low energy consumption.

[0008] Catalytic cracking is a promising alternative to conventional non-catalytic pyrolysis reactions, overcoming the existing problems of waste plastic pyrolysis oil. Catalytic cracking utilizes waste plastic pyrolysis oil, which consists of a wide range of carbon atoms and contains a large amount of olefins, as a feedstock, enabling the production of high-yield, high-value-added chemicals with relatively low energy consumption. However, the coke generated during the cracking process causes rapid catalyst deactivation, limiting its continuous use. Therefore, a reactor equipped with a continuous catalyst regeneration system, such as a circulating fluidized bed reactor, is required. Zeolite-based catalysts, particularly ZSM-5, are known to be excellent catalysts for cracking pyrolysis oil. However, to selectively produce high-yield, high-value-added chemicals, controlling the acidity of the catalyst and ensuring its hydrothermal stability are essential. Furthermore, securing optimal operating conditions (reaction temperature, space velocity, etc.) is also crucial.

[0009] The present disclosure provides a method for manufacturing high value-added chemicals from waste plastics, which is environmentally friendly by reducing greenhouse gas emissions by manufacturing high value-added chemicals from waste plastics, utilizes the entire oil-containing stream produced by pyrolyzing waste plastic raw materials, simplifies the process by eliminating a separate removal process for olefins or non-hydrocarbon substances contained in the oil-containing stream, significantly improves the yield of high value-added chemicals, enables continuous operation, and improves process economics by reducing energy consumption.

[0010] Additionally, the present disclosure seeks to improve the yield of high value-added chemicals and further control the content ratio of ethylene, propylene, butylene or BTXs.

[0011] The present disclosure provides a method for producing an oil-containing stream by pyrolyzing waste plastic raw materials, comprising: a) generating an oil-containing stream by pyrolyzing waste plastic raw materials;

[0012] b) reacting part or all of the oil-containing stream in the presence of a catalyst in at least one circulating fluidized bed reactor;

[0013] c) a step of separating and recovering high value-added chemicals from the reaction product;

[0014] A method for producing a high value-added chemical from waste plastic is provided, wherein the oil-containing stream produced in step a) is fed into the reactor in step b) without a process for removing olefins and non-hydrocarbon substances, and the catalyst includes zeolite and a metal.

[0015] In one embodiment, the zeolite may include at least one selected from the group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-48, zeolite X, zeolite Y, zeolite-L, zeolite-β, zeolite-Ω, mordenite, erionite, chabazite, and MFI zeolite.

[0016] In one embodiment, the metal may include one or more metals selected from Cu, Ag, La, Ga, and Ni.

[0017] In one embodiment, the metal may include one or more metals selected from Cu, Ag, and Ni.

[0018] In one embodiment, the catalyst may include a metal loaded at 1 to 10 wt%.

[0019] In one embodiment, the zeolite may include a zeolite into which phosphorus (P) has been introduced.

[0020] In one embodiment, the zeolite may be pre-steamed.

[0021] In one embodiment, the oil-containing stream may comprise 20 to 60 wt% olefins, 5 to 30 wt% aromatic hydrocarbons, and 15 to 40 wt% naphtha-based hydrocarbons.

[0022] In one embodiment, the oil-containing stream may comprise 100 to 7000 ppm of nitrogen components, 10 to 3000 ppm of sulfur components, and 1 to 5000 ppm of halogen components.

[0023] In one embodiment, the method may further include the step of contacting the oil-containing stream with one or more adsorbents selected from activated carbon, ion exchange resin, silica gel, clay, zeolite, molecular sieve, activated aluminum oxide, and layered double hydroxide.

[0024] In one embodiment, step b) may be performed in a circulating fluidized bed reactor comprising a reactor, a stripper and a regenerator.

[0025] In one embodiment, the high value-added chemical may include ethylene + propylene or C2-C4 olefin or C2-C4 olefin + BTXs.

[0026] In one embodiment, the yield of ethylene + propylene may be 40% to 50%, the yield of C2-C4 olefins may be 40% to 60%, or the yield of C2-C4 olefins + BTXs may be 50% to 80%, based on 100 wt% of the oil-containing stream.

[0027] In one embodiment, the reaction may be performed at a reaction temperature of 590 to 720°C.

[0028] In one embodiment, the reaction is carried out at a weight hourly space velocity (WHSV), defined as the ratio of the mass flow rate of the oil-containing stream to the mass of the catalyst, of 10 h -1 Within 20 h -1 It may be performed by.

[0029] The method for producing high-value-added chemicals from waste plastic according to the present disclosure is environmentally friendly by reducing greenhouse gas emissions, and utilizes the entire oil-containing stream generated by pyrolysis of waste plastic raw materials. Furthermore, the process is simplified by eliminating the need for a separate removal process for olefins or non-hydrocarbon substances contained in the oil-containing stream. The yield of high-value-added chemicals is significantly increased, continuous operation is possible, and energy consumption is reduced, thereby improving process economics.

[0030] In particular, the method for producing a high value-added chemical substance from waste plastic according to the present disclosure can prevent catalyst deactivation by steam at high temperatures during catalyst regeneration by carrying out a reaction in the presence of a catalyst to which phosphorus (P) has been introduced, and can achieve a remarkably excellent yield of a high value-added chemical substance by using the catalyst to which phosphorus (P) has been introduced after pre-steaming.

[0031] In addition, the method for producing high value-added chemicals from waste plastics according to the present disclosure can improve the yield of high value-added chemicals by loading metals into the catalyst, and additionally, the content ratios of ethylene, propylene, butylene, or BTXs can be selected and controlled by the user.

[0032] Figure 1 is an SEM photograph of a catalyst manufactured according to Manufacturing Example 2 below.

[0033] Figure 2 is a schematic diagram showing an example of a circulating fluidized bed reactor according to the present disclosure.

[0034] Hereinafter, a method for producing high value-added chemicals from waste plastic according to the present disclosure is described in detail.

[0035] Unless otherwise defined, the technical and scientific terms used herein have the meaning commonly understood by a person of ordinary skill in the art to which this invention pertains, and in the following description, descriptions of known functions and configurations that may unnecessarily obscure the gist of the present disclosure are omitted.

[0036] Additionally, the singular forms used herein may be intended to include the plural forms as well, unless the context specifically indicates otherwise.

[0037] In addition, units used in this specification without special mention are based on weight, for example, units of % or ratio mean weight% or weight ratio, and weight% means the weight% that any one component of the entire waste mixture occupies in the waste mixture unless otherwise defined.

[0038] Additionally, the numerical ranges used herein include lower and upper limits and all values ​​within that range, increments logically derived from the shape and width of the defined range, all doubly defined values, and all possible combinations of upper and lower limits of numerical ranges defined in different shapes. Unless otherwise specifically defined in the specification of the present disclosure, values ​​outside the numerical range that may arise due to experimental error or rounding of values ​​are also included in the defined numerical range.

[0039] The term "includes" in this specification is an open-ended description equivalent to expressions such as "comprises," "contains," "has," or "characterizes," and does not exclude additional elements, materials, or processes not listed.

[0040] The term 'Weight Hourly Space Velocity (WHSV)' in this specification is defined as the ratio of the mass flow rate of the oil-containing stream to the mass of the catalyst.

[0041] The term 'high value-added chemicals' in this specification is a comprehensive term that refers to C2-C4 olefins (ethylene, propylene, butadiene, etc.) and BTXs (benzene, toluene, xylene, ethylbenzene, and styrene), all of which are important raw materials in the petrochemical industry and serve as the basis for various plastics and other chemical products.

[0042] The above high value-added chemical substances may include polymer monomers, polymer raw materials, etc.

[0043] Hereinafter, a method for producing high value-added chemicals from waste plastic according to the present disclosure is described in detail.

[0044] The present disclosure provides a method for producing a high value-added chemical from waste plastic, comprising the steps of: a) pyrolyzing a waste plastic raw material to produce an oil-containing stream; b) reacting at least a portion of the oil-containing stream in the presence of a catalyst in at least one circulating fluidized bed reactor; c) separating and recovering a high value-added chemical from the reaction product; wherein the oil-containing stream produced in step a) is fed into the reactor of step b) without a process for removing olefins and non-hydrocarbon substances.

[0045] The method for producing high-value-added chemicals from waste plastic according to the present disclosure reduces greenhouse gas emissions by producing high-value-added chemicals from waste plastic, thereby being environmentally friendly. Furthermore, the entire oil-containing stream generated by pyrolysis of waste plastic raw materials can be utilized. Furthermore, the process can be simplified by eliminating the need for a separate removal process for olefins or non-hydrocarbon substances contained in the oil-containing stream. Furthermore, the yield of high-value-added chemicals can be significantly increased, thereby enhancing process economics.

[0046] In particular, the method for producing high-value-added chemicals from waste plastic according to the present disclosure can be configured without a process for removing olefins or non-hydrocarbon substances such as nitrogen, sulfur, oxygen, and halogen components, even if the oil-containing stream produced by pyrolysis of waste plastic raw materials contains such substances. Therefore, the method has the advantage of enabling process simplification and construction of a process with improved process economics.

[0047] The above step a) is a step of pyrolyzing waste plastic raw materials, which is a process of converting waste plastic into an oil-containing stream including hydrocarbon products within a pyrolysis unit.

[0048] The above waste plastic may specifically include, but is not limited to, polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), etc.

[0049] The above oil-containing stream is produced by pyrolysis of waste plastic raw materials, and may further be mixed with biomass pyrolysis oil, recycled lubricating oil, high-chlorine content crude oil, Fisher-Tropsch process product, or a mixture thereof as needed.

[0050] The above step a) may use a pyrolysis method using a batch reactor, for example, a rotary quill type batch reactor, and pyrolysis may be performed after uniformly melting the waste plastic, but is not limited thereto.

[0051] The above step a) may include, but is not limited to, a pretreatment step for the purpose of removing impurities, etc. and an additive injection step.

[0052] In one embodiment, the method may further comprise the step of filtering the oil-containing stream through a filter.

[0053] In one embodiment, the method may further comprise the step of contacting the oil-containing stream with any one adsorbent selected from activated carbon, ion exchange resin, silica gel, clay, zeolite, molecular sieve, activated aluminum oxide, and layered double hydroxide.

[0054] The method further includes a step of contacting the oil-containing stream with any one adsorbent selected from activated carbon, ion exchange resin, silica gel, clay, zeolite, molecular sieve, activated aluminum oxide, and layered double hydroxide, thereby removing solid components contained in the oil-containing stream or substances that can be easily converted to coke in the reactor before being fed into the reactor of step b), thereby promoting stable process operation and achieving the desired process yield.

[0055] The above step a) may be performed at a temperature of 700°C or less, 200 to 600°C, 350 to 500°C, or 400 to 500°C. In addition, the above step a) may be performed at a pressure of 0 to 3 bar,g or 0 to 0.3 bar,g, but is not limited thereto.

[0056] The above step a) may be thermal decomposition for 30 minutes to 16 hours, preferably 3 hours to 10 hours, but is not limited thereto.

[0057] In one embodiment, the oil-containing stream may comprise 1 to 80 wt%, 10 to 70 wt%, or 20 to 60 wt% olefin.

[0058] In one embodiment, the oil-containing stream may comprise olefins in an amount of at least 10 wt%, at least 20 wt%, at least 30 wt%, at least 40 wt%, at least 50 wt%, or at least 55 wt%, and may comprise olefins in an amount of at most 80 wt%, at most 70 wt%, or at most 60 wt%, and may also comprise 1 to 80 wt%, 10 to 70 wt%, 20 to 60 wt%, 30 to 60 wt%, 40 to 60 wt%, 50 to 60 wt%, or 55 to 60 wt%, but is not limited thereto.

[0059] In one embodiment, the oil-containing stream comprises C5-C 12 The content of hydrocarbons in the naphtha region composed of hydrocarbons may be at least 1 wt%, at least 3 wt%, at least 5 wt%, at least 7 wt%, at least 8 wt%, at least 9 wt%, at least 10 wt%, or at least 11 wt%, and may be at most 50 wt%, at most 45 wt%, at most 40 wt%, at most 30 wt%, at most 20 wt%, or at most 16 wt%, and the oil-containing stream may contain 1 to 50 wt%, 10 to 45 wt%, or 15 to 40 wt% of hydrocarbons in the naphtha region composed of C5-C12 hydrocarbons.

[0060] In one embodiment, the oil-containing stream may simultaneously comprise 20 to 60 wt% olefins, 5 to 30 wt% aromatic hydrocarbons, and 15 to 40 wt% naphtha hydrocarbons composed of C5-C9 hydrocarbons.

[0061] The above non-hydrocarbon material may include, but is not limited to, at least one material selected from the group consisting of nitrogen-containing material, sulfur-containing material, oxygen-containing material, and halogen-containing material.

[0062] In one embodiment, the oil-containing stream may comprise 100 to 7000 ppm of nitrogen component.

[0063] In one embodiment, the oil-containing stream may comprise 10 to 3000 ppm of sulfur components.

[0064] In one embodiment, the oil-containing stream may comprise 0.01 to 4 wt% of an oxygen component.

[0065] In one embodiment, the oil-containing stream may comprise 1 to 5000 ppm of halogen components.

[0066] In one embodiment, the oil-containing stream may simultaneously contain 100 to 7000 ppm of nitrogen components, 10 to 3000 ppm of sulfur components, 0.01 to 4 wt% of oxygen components, and 1 to 5000 ppm of halogen components.

[0067] The above step b) is a step of catalytic cracking the oil-containing stream, which is a process of converting the oil-containing stream into a high value-added chemical substance within a reactor.

[0068] In one embodiment, step b) may be performed in the presence of a catalyst within at least one circulating fluidized bed reactor, but is not limited thereto.

[0069] In one embodiment, step b) may be performed in a circulating fluidized bed reactor including a reactor, a stripper, and a regenerator, but is not limited thereto.

[0070] When the step b) above is performed in a circulating fluidized bed reactor, the method for producing a high value-added chemical from waste plastic according to the present disclosure utilizes the entire oil-containing stream produced by pyrolyzing the waste plastic raw material, and simplifies the process by eliminating the removal process of olefins or non-hydrocarbon substances contained in the oil-containing stream. In addition, due to the structural characteristics of the circulating fluidized bed reactor, the residence time of the reaction product in the reactor is short, so that the yield of the high value-added chemical is significantly improved, and coke on the catalyst is continuously removed, so that a process with significantly improved economic feasibility can be constructed.

[0071] In one embodiment, the reactor may be one in which steam is injected as a moving gas together with an oil-containing stream produced by pyrolyzing waste plastic raw materials into the reactor.

[0072] In the step b), the reaction may be performed at 900°C or less, 800°C or less, 750°C or less, 720°C or less, 700°C or less, or 680°C or less. In addition, in the step b), the reaction may be performed at 300°C or more, 400°C or more, 450°C or more, 500°C or more, 540°C or more, 550°C or more, 570°C or more, 580°C or more, 590°C or more, 600°C or more, 620°C or more, 640°C or more, or 650°C or more. The step b) may be performed at 500 to 800°C, 520 to 750°C, or 590 to 720°C.

[0073] If the reaction temperature is below 590℃, the oil-containing stream generated by thermal decomposition of waste plastic raw materials is not sufficiently converted into high value-added chemicals, and if it exceeds 720℃, the high value-added chemicals generated may be converted into aromatic hydrocarbons or coke due to excessive secondary reactions, which may cause a problem of a decrease in the yield of high value-added chemicals.

[0074] The above reaction is carried out at a weight hourly space velocity (WHSV) of 1 to 100 h, which is defined as the ratio of the mass flow rate of the oil-containing stream to the mass of the catalyst. -1 , 1 to 80 h -1 , 1 to 70 h -1 , 1 to 60 h -1 , 2 to 60 h -1 , 2 to 50 h -1 3 to 50 h -1 , 4 to 48 h -1 , 6 to 24 h -1 or 10 to 20 h -1 can be performed.

[0075] Space velocity is 24 h -1 If it exceeds 6 h, the oil-containing stream produced by pyrolysis of waste plastic raw materials is not sufficiently converted into high value-added chemicals. -1 If it is less than this, the high value-added chemicals generated by excessive secondary reactions may be converted into aromatic hydrocarbons or coke, which may cause a problem of reduced yield of high value-added chemicals.

[0076] The catalyst may be zeolite, clay, SAPO (silica-alumina-phosphate), ALPO (aluminum phosphate), MOF (Metal Organic Framework), amorphous silica-alumina, or a mixture thereof. Furthermore, waste zeolite, waste clay, etc. may be utilized as is or after simple treatment to further improve activity. In order to use the waste zeolite, waste clay, etc. as a catalyst, air combustion may be performed to remove coke, or solvent treatment may be performed to remove oil.

[0077] The above zeolite may include at least one selected from the group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-48, zeolite X, zeolite Y, zeolite-L, zeolite-β, zeolite-Ω, mordenite, erionite, chabazite, and MFI zeolite.

[0078] The catalyst may further comprise a carrier or binder comprising carbon, an alkaline earth metal oxide, an alkali metal oxide, alumina, silica, silica-alumina, zirconia, titania, silicon carbide, niobia, aluminum phosphate, alumina hydrate or a mixture thereof.

[0079] In one embodiment, the catalyst may have phosphorus (P) introduced therein.

[0080] The method for producing a high value-added chemical substance from waste plastic according to the present disclosure can prevent catalyst deactivation by steam during catalytic reaction or regeneration in the process by carrying out a reaction in the presence of a catalyst to which phosphorus (P) has been introduced, thereby maintaining an excellent yield of high value-added chemical substances.

[0081] In one embodiment, the catalyst may be metal-loaded.

[0082] The method for producing a high value-added chemical from waste plastic according to the present disclosure can further improve the content of the high value-added chemical by additionally loading the metal into the catalyst into which the phosphorus has been introduced.

[0083] By additionally loading a certain amount of metal into the catalyst into which the above-mentioned phosphorus has been introduced, there is a remarkable effect of further increasing the content of high value-added chemicals, and the content may be, as an upper limit, 0.1 wt% or more, 1 wt% or more, 2 wt% or more, 3 wt% or more, and as a lower limit, 10 wt% or less, 9 wt% or less, 8 wt% or less, 7 wt% or less, 6 wt% or less, 5 wt% or less, or 0.1 to 10 wt%, 1 to 10 wt%, 1 to 5 wt%, 2 to 5 wt%, but is not limited thereto.

[0084] The metal may include at least one metal selected from Cu, Ag, La, Ga, and Ni, and in order to selectively improve the yield of ethylene and propylene among the high value-added chemical contents, at least one may be selected from Cu, Ag, and Ni, and in order to selectively improve the yield of ethylene, propylene, and butylene among the high value-added chemical contents, at least one may be selected from Cu, Ag, La, Ga, and Ni, and in order to selectively improve the yield of ethylene, propylene, butylene, and BTXs among the high value-added chemical contents, at least one may be selected from Cu, Ag, and Ni, but is not limited thereto.

[0085] In addition, by loading the above metal, high value-added chemicals can be stably produced for a long period of time, and in particular, by loading one or more metals selected from Cu, Ag, La, Ga and Ni, the yield of high value-added chemicals can be controlled, and at the same time, the yield of hydrogen generated also increases, which has the advantage of being increased.

[0086] This may be advantageous in obtaining hydrogen raw materials due to the recent development of hydrogen energy.

[0087] In one embodiment, the catalyst may be pre-steamed.

[0088] The method for producing high value-added chemicals from waste plastic according to the present disclosure can achieve a significantly superior yield of high value-added chemicals by using a catalyst in which phosphorus (P) is introduced and subjected to a pre-steaming treatment. That is, compared to the case where a catalyst is not pre-steamed, the use of a catalyst subjected to a pre-steaming treatment exhibits a significantly superior yield of high value-added chemicals.

[0089] In one embodiment, the catalyst may be a spherical or oval shaped body.

[0090] Additionally, in one embodiment, the catalyst may have a diameter of 1 μm or more, 5 μm or more, 10 μm or more, 20 μm or more, 30 μm or more, 40 μm or more, 50 μm or more, 60 μm or more, or 70 μm or more. Additionally, the catalyst may have a diameter of 500 μm or less, 400 μm or less, 300 μm or less, 250 μm or less, 200 μm or less, or 150 μm or less. The catalyst may have a diameter of 30 μm to 200 μm or 50 μm to 150 μm.

[0091] If the catalyst diameter is less than 50 ㎛, the oil-containing stream generated by pyrolysis of waste plastic raw materials may not be sufficiently converted into high value-added chemicals due to the short residence time in the reactor, or separation of the catalyst and product after the reaction may be difficult. In addition, if the catalyst diameter is greater than 150 ㎛, the catalyst flow in the reactor may not be smooth, or problems of catalyst wear during flow may occur.

[0092] In one embodiment, the high value-added chemical may be, but is not limited to, ethylene, propylene, or a C2-C4 olefin or a C2-C4 olefin + BTXs.

[0093] In one embodiment, the yield of the high value-added chemical may be the yield of the high value-added chemical generated based on 100 wt% of the oil-containing stream of step a).

[0094] According to one embodiment, the yield of ethylene generated in the present disclosure may be a lower limit of 15% or more, 16% or more, 17% or more, 18% or more, 19% or more, and 20% or more, and an upper limit of 30% or less, 27% or less, 25% or less, 23% or less, and 21% or less, based on 100 wt% of the oil-containing stream of step a).

[0095] According to one embodiment, the yield of propylene generated in the present disclosure may be a lower limit of 15% or more, 17% or more, 20% or more, 21% or more, 22% or more, 23% or more, 24% or more, 25% or more, 26% or more, or 27% or more, and an upper limit of 35% or less, 30% or less, 29% or less, or 28% or less, based on 100 wt% of the oil-containing stream of step a).

[0096] According to one embodiment, the yield of C4 olefins generated in the present disclosure may be a lower limit of 10% or more, 11% or more, 12% or more, 13% or more, or 14% or more, and an upper limit of 20% or less, 17% or less, 16% or less, or 15% or less, based on 100 wt% of the oil-containing stream of step a).

[0097] According to one embodiment, the yield of BTXs generated in the present disclosure may be a lower limit of 5% or more, 6% or more, 7% or more, 8% or more, 9% or more, 10% or more, 11% or more, 12% or more, 13% or more, 14% or more, 15% or more, 16% or more, or 17% or more, and an upper limit of 30% or less, 25% or less, 20% or less, 19% or less, or 18% or less, based on 100 wt% of the oil-containing stream of step a).

[0098] According to one embodiment, the yield of hydrogen generated in the present disclosure may be a lower limit of 0.23% or more, 0.24% or more, 0.25% or more, 0.30% or more, 0.35% or more, 0.40% or more, or 0.42% or more, and an upper limit of 1% or less, 0.7% or less, or 0.5% or less, based on 100 wt% of the oil-containing stream of step a).

[0099] In addition, according to one embodiment, the ethylene+propylene yield generated in the present disclosure may be a lower limit of 40% or more, 41% or more, 42% or more, 43% or more, 44% or more, 45% or more, 46% or more, or 47% or more, and an upper limit of 50% or less, 49% or less, or 48% or less, based on 100 wt% of the oil-containing stream of step a).

[0100] In addition, according to one embodiment, the C2-C4 olefin yield generated in the present disclosure may be a lower limit of 40% or more, 45% or more, 50% or more, 55% or more, 56% or more, 57% or more, or 58% or more, and an upper limit of 65% or less, 60% or less, or 59% or less, based on 100 wt% of the oil-containing stream of step a).

[0101] In addition, according to one embodiment, the yield of C2-C4 olefins + BTXs generated in the present disclosure may be a lower limit of 50% or more, 60% or more, 61% or more, 62% or more, 63% or more, 64% or more, 65% or more, 66% or more, 67% or more, 68% or more, 69% or more, 70% or more, 71% or more, 72% or more, 73% or more, 74% or more, 75% or more, and an upper limit of 80% or less, 79% or less, 78% or less, 77% or less, 76% or less, based on 100 wt% of the oil-containing stream of step a).

[0102]

[0103] The present disclosure will be described in more detail based on the following examples and comparative examples. However, the following examples and comparative examples are merely illustrative examples for further explaining the present disclosure, and the present disclosure is not limited by the following examples and comparative examples. Unless otherwise specified in the present invention, all temperatures are expressed in degrees Celsius, and unless otherwise specified, the amount of composition used is expressed in weight percent.

[0104]

[0105] [Manufacturing Example 1 - ZSM-5 Synthesis]

[0106] Solution 1 was prepared by adding 29.51 g of distilled water to 36.83 g of water glass and stirring for 30 minutes. In addition, solution 2 was prepared by mixing 3.95 g of aluminum sulfate, 0.19 g of sulfuric acid, and 29.51 g of distilled water and stirring for 20 minutes. Next, solution 2 was added to solution 1, stirred, placed in a Teflon container, and hydrothermally synthesized at 170 ℃ for 24 hours and then cooled to room temperature. After cooling, 50 g of 10 wt% ammonium sulfate solution was mixed with 4 g of ZSM-5 zeolite recovered through filtration and washing processes, stirred for 30 minutes, and then washing and filtering processes were performed three times in succession to perform ion exchange, thereby producing ZSM-5.

[0107] Phase analysis of the product obtained by the above-described method can be performed by collecting data at 2θ 7-9° and 22-25° corresponding to the characteristic peaks of ZSM-5 using an X-ray diffraction analyzer (e.g., Rigaku Model D / Max III). It was confirmed from the analyzed X-ray diffraction pattern that the prepared zeolite had a ZSM-5 crystal structure.

[0108]

[0109] [Manufacturing Example 2 - Manufacturing of Pre-Steamed P / ZSM-5 Molded Catalyst]

[0110] In Manufacturing Example 1, 165.25 g of ZSM-5 (Si / Al = 11) synthesized was slowly added to 321.23 g of distilled water while stirring to prepare a slurry, then 71.47 g of 85% phosphoric acid was additionally added and stirred at room temperature for 30 minutes. A solution of 277.54 g of boehmite (Al2O3 content 72 wt%) dispersed in a 2% nitric acid solution was further added to the slurry, stirred for 1 hour, then 166.5 g of clay was added and thoroughly mixed for 2 hours using a high-viscosity slurry mixer. The slurry was spray-molded to obtain microspheres with a particle size of 75-200 ㎛, and calcined at 650 °C for 5 hours. After calcination, a P / ZSM-5 molded catalyst was obtained. The obtained P / ZSM-5 molded catalyst was loaded into a steam treatment reactor, and distilled water was injected at a rate of 5 cc / min using a liquid pump, vaporized, and brought into contact with the sample in the form of steam at 760°C for 24 hours in a 100% steam atmosphere, thereby obtaining a pre-steamed P / ZSM-5 molded catalyst.

[0111]

[0112] [Manufacturing Example 3 - Preparation of a Pre-Steamed 2wt%Cu-P / ZSM5 Molded Catalyst]

[0113] A 2 wt% Cu-P / ZSM5 molded catalyst with 2 wt% Cu loading was manufactured by impregnating 20 g of the P / ZSM-5 molded catalyst obtained in Manufacturing Example 2 with an aqueous solution of 1.536 g Cu(NO3)23H2O, a Cu precursor, dissolved in 5.169 g of distilled water, using an incipient wetness impregnation method, and calcining at 650°C for 5 hours. After calcination, a 2 wt% Cu-P / ZSM5 molded catalyst was obtained. The obtained 2 wt% Cu-P / ZSM5 molded catalyst was loaded into a steam treatment reactor, and distilled water was injected at a rate of 5 cc / min using a liquid pump, vaporized, and brought into contact with the sample in the form of steam at 760°C for 24 hours in a 100% steam atmosphere, thereby obtaining a pre-steamed 2 wt% Cu-P / ZSM5 molded catalyst.

[0114]

[0115] [Manufacturing Example 4 - Preparation of a Pre-Steamed 2wt%Ag-P / ZSM5 Molded Catalyst]

[0116] Manufacturing Example 3 was performed in the same manner as Manufacturing Example 3, except that the metal precursor was changed from a Cu precursor to an Ag precursor of 0.636 g AgNO3.

[0117]

[0118] [Manufacturing Example 5 - Preparation of a Pre-Steamed 2wt%La-P / ZSM5 Molded Catalyst]

[0119] Manufacturing Example 3 was performed in the same manner as Manufacturing Example 3, except that the metal precursor was changed from a Cu precursor to a La precursor of 0.636 g La(NO3)3*xH2O.

[0120]

[0121] [Manufacturing Example 6 - Preparation of a Pre-Steamed 2wt%Ga-P / ZSM5 Molded Catalyst]

[0122] Manufacturing Example 3 was performed in the same manner as Manufacturing Example 3, except that the metal precursor was changed from a Cu precursor to a Ga precursor of 1.469 g Ga(NO3)3*xH2O.

[0123]

[0124] [Manufacturing Example 7 - Preparation of a pre-steamed 2 wt% Ni-P / ZSM5 molded catalyst]

[0125] Manufacturing Example 4 was performed in the same manner as Manufacturing Example 3, except that the metal precursor was changed from a Cu precursor to a Ni precursor of 2.022 g Ni(NO3)2*6H2O.

[0126]

[0127] [Manufacturing Example 8 - Preparation of pre-steamed 1 wt% Ag-P / ZSM5 molded catalysts]

[0128] Manufacturing Example 3 was performed in the same manner as Manufacturing Example 3, except that the content of AgNO3, which is an Ag precursor, was changed to 0.318 g, thereby changing the Ag content to 1 wt%.

[0129]

[0130] [Manufacturing Example 9 - Preparation of pre-steamed 3 wt% Ag-P / ZSM5 molded catalysts]

[0131] Manufacturing Example 3 was performed in the same manner as Manufacturing Example 3, except that the content of AgNO3, which is an Ag precursor, was changed to 0.954 g, thereby changing the Ag content to 3 wt%.

[0132]

[0133] [Manufacturing Example 10 - Preparation of Pre-Steamed 4wt%Ag-P / ZSM5 Molded Catalysts]

[0134] Manufacturing Example 3 was performed in the same manner as Manufacturing Example 3, except that the content of AgNO3, which is an Ag precursor, was changed to 1.272 g, thereby changing the Ag content to 4 wt%.

[0135]

[0136] [Manufacturing Example 11 - Preparation of Pre-Steamed 5wt%Ag-P / ZSM5 Molded Catalysts]

[0137] Manufacturing Example 3 was performed in the same manner as Manufacturing Example 3, except that the content of AgNO3, which is an Ag precursor, was changed to 1.591 g, thereby changing the Ag content to 5 wt%.

[0138]

[0139] [Example 1]

[0140] a) Mixed waste plastics, which are mainly composed of polyolefin waste plastics (PE and PP) and a mixture of various plastics, were fed into a rotary quill reactor and pyrolyzed in an oxygen-free atmosphere to produce an oil-containing stream. Fuel was supplied to the bottom of the rotating reactor and combusted to heat the reactor to an internal temperature of 350 to 500°C. At this time, the gas discharged through pyrolysis was condensed to have a density of 0.812 g / cm. 3 , and an oil-containing stream having a viscosity of 4.0 cP at 23.6°C was produced.

[0141] b) The above oil-containing stream was fed into a simulated fluidized bed reactor loaded with 3 g of catalyst and catalytic cracking was performed. (Feed injection rate 0.8 g / min, reaction temperature 680 ℃, space velocity (WHSV) 16 h -1 , reaction time 90 seconds)

[0142] At this time, the catalyst used was the catalyst manufactured by the above manufacturing example 3.

[0143] c) The reaction product was separated into high value-added chemicals using a conventional fractional distillation method, and each was recovered. The recovered ethylene yield, propylene yield, C4 olefin yield, and BTX yield, calculated based on 100 wt% of the input oil-containing stream, are shown in Table 1.

[0144]

[0145] [Example 2]

[0146] The same procedure as Example 1 was followed, except that the catalyst manufactured by Manufacturing Example 4 was used as the catalyst.

[0147]

[0148] [Example 3]

[0149] The same procedure as Example 1 was followed, except that the catalyst manufactured by Manufacturing Example 5 was used as the catalyst.

[0150]

[0151] [Example 4]

[0152] The same procedure as Example 1 was followed, except that the catalyst manufactured by Manufacturing Example 6 was used as the catalyst.

[0153]

[0154] [Example 5]

[0155] The same procedure as Example 1 was followed, except that the catalyst manufactured by Manufacturing Example 7 was used as the catalyst.

[0156]

[0157] [Example 6]

[0158] The same procedure as Example 1 was followed, except that the catalyst manufactured by Manufacturing Example 8 was used as the catalyst.

[0159]

[0160] [Example 7]

[0161] The same procedure as Example 1 was followed, except that the catalyst manufactured by Manufacturing Example 9 was used as the catalyst.

[0162]

[0163] [Example 8]

[0164] The same procedure as Example 1 was followed, except that the catalyst manufactured by Manufacturing Example 10 was used as the catalyst.

[0165]

[0166] [Example 9]

[0167] The same procedure as Example 1 was followed, except that the catalyst manufactured by Manufacturing Example 11 was used as the catalyst.

[0168]

[0169] [Comparative Example 1]

[0170] The same procedure as Example 1 was followed, except that the catalyst manufactured by Manufacturing Example 2 was used as the catalyst.

[0171]

[0172] [Comparative Example 2]

[0173] The same procedure as Example 1 was followed, except that thermal decomposition was performed without using a catalyst in the reactor.

[0174]

[0175] Ethylene Propylene C4 Olefin BTXs Methane C2-C4 Paraffin C2~C4 Olefin Example 1 19.10 27.00 12.30 17.00 6.106.00 58.40 Example 2 19.26 26.94 12.07 16.3 35.9 15.8 0 58.27 Example 3 16.70 26.20 14.70 11.90 6.70 5.40 57.60 Example 4 16.87 26.18 14.29 5.5 36.23 5.21 5 7.34 Example 5 18.3 125.56 12.93 15.23 6.66 5.43 56.80 Comparative Example 116.9026.2013.2015.405.605.1056.30Comparative example 213.6014.108.3011.206.004.9036.00

[0176]

[0177] In the above Table 1, C4 olefins means the sum of the yields of 1-butene, isobutene, 2-butene, and 1,3-butadiene; BTXs means the sum of the yields of benzene, toluene, xylene, ethylbenzene, and styrene; C2-C4 paraffins means the sum of the yields of ethane, propane, normal butane, and isobutane; and C2~C4 olefins means the sum of the yields of ethylene, propylene, and C4 olefins.

[0178] As shown in the results in Table 1 above, it was confirmed that when Cu, Ag, La, Ga, and Ni metals were loaded onto the P / ZSM-5 molded catalyst, a higher C2~C4 olefin yield could be obtained compared to the P / ZSM-5 molded catalyst without metal.

[0179]

[0180] Ethylene Propylene C4 Olefin BTXs Methane C2-C4 Paraffin C2~C4 Olefin Example 6 18.87 26.81 12.25 16.22 6.14 5.75 7.93 Example 2 19.26 26.94 12.07 16.33 5.915.80 58.27 Example 7 20.25 26.67 11.49 17.17 6.16 15 8.41 Example 8 20.82 26.77 11.35 15.76 04 6.65 8.94 Example 9 20.39 26.64 11.65 15.74 6.13 6.45 8.68 Comparative Example 116.9026.2013.2015.405.605.1056.30Comparative example 213.6014.108.3011.206.004.9036.00

[0181]

[0182] As shown in the results in Table 2 above, the 4 wt% Ag-P / ZSM-5 molded catalyst showed the best C2~C4 olefin yield among the Ag-P / ZSM-5 molded catalysts, and excellent C2~C4 olefin yields were shown in the order of 4 wt%, 5 wt%, 3 wt%, 2 wt%, and 1 wt% Ag loading. Therefore, it was confirmed that the C2~C4 olefin yield was reduced when the Ag content was too low or too high.

[0183]

[0184] Catalyst used Ethylene + Propylene C2~C4 Olefin C2~C4 Olefin + BTX Hydrogen Example 1 2 wt% Cu-P / ZSM-5 (Preparation Example 3) 46.10 5 8.47 5.40 0.42 Example 2 2 wt% Ag-P / ZSM-5 (Preparation Example 4) 46.20 5 8.27 7 4.60 0.32 Example 3 2 wt% La-P / ZSM-5 (Preparation Example 5) 42.90 5 7.66 9.50 0.24 Example 4 2 wt% Ga-P / ZSM-5 (Preparation Example 6) 43.05 5 7.34 6 2.87 0.24 Example 5 2 wt% Ni-P / ZSM-5 (Preparation Example 7)43.8756.8072.030.40Example 61wt%Ag-P / ZSM-5 (Preparation Example 8)45.6857.9374.150.32Example 73wt%Ag-P / ZSM-5 (Preparation Example 9)46.9258.4175.580.34Example 84wt%Ag-P / ZSM-5 (Preparation Example 10)47.5958.9474.640.39Example 95wt%Ag-P / ZSM-5 (Preparation Example 11)47.0358.6874.420.38Comparative Example 1P / ZSM-5 (Preparation Example 2)43.1056.3071.700.23Comparative Example 2Catalyst None27.7036.0047.200.20

[0185]

[0186] Table 3 is a table that summarizes ethylene + propylene, C2-C4 olefin, and C2-C4 olefin + BTXs according to the catalysts of the examples and comparative examples of Tables 1 and 2.

[0187]

[0188] In summary, when the catalyst contains Ag, Cu, and Ni, the content of ethylene + propylene or the content of C2-C4 olefin + BTXs was measured to be higher than that of Comparative Examples 1, 2, and Examples 3 and 4, and the C2-C4 olefin content of Examples 1 to 9 was measured to be higher than that of Comparative Examples 1 and 2.

[0189] This shows that the content of high value-added chemicals can be controlled by the metal loaded into the catalyst.

[0190]

[0191] While the preferred embodiments of the present disclosure have been described above, it is clear that the present disclosure is capable of various modifications and equivalent scopes, and that the above embodiments can be appropriately modified and applied in the same manner. Therefore, the above description does not limit the scope of the present disclosure, which is defined by the following claims.

Claims

1. a) A step of pyrolyzing waste plastic raw materials to produce an oil-containing stream; b) reacting part or all of the oil-containing stream in the presence of a catalyst in at least one circulating fluidized bed reactor; c) a step of separating and recovering high value-added chemicals from the reaction product; A method for producing a high value-added chemical from waste plastic, wherein the oil-containing stream produced in step a) is fed into the reactor in step b) without a process for removing olefins and non-hydrocarbon substances, and the catalyst includes zeolite and a metal.

2. In paragraph 1, A method for producing a high value-added chemical from waste plastic, wherein the zeolite comprises at least one selected from the group consisting of ZSM-5, ZSM-11, ZSM-12, ZSM-22, ZSM-23, ZSM-48, zeolite X, zeolite Y, zeolite-L, zeolite-β, zeolite-Ω, mordenite, erionite, chabazite, and MFI zeolite.

3. In paragraph 1, A method for producing a high value-added chemical substance from waste plastic, wherein the metal comprises at least one metal selected from Cu, Ag, La, Ga, and Ni.

4. In paragraph 3, A method for producing a high value-added chemical substance from waste plastic, wherein the metal comprises at least one metal selected from Cu, Ag, and Ni.

5. In paragraph 1, A method for producing high value-added chemicals from waste plastics, comprising loading the catalyst with 1 to 10 wt% of metal.

6. In paragraph 1, A method for producing a high value-added chemical substance from waste plastic, wherein the above zeolite comprises a zeolite into which phosphorus (P) has been introduced.

7. In paragraph 6, A method for producing high value-added chemicals from waste plastic, wherein the above zeolite is pre-steamed.

8. In paragraph 1, A method for producing high value-added chemicals from waste plastics, wherein the oil-containing stream comprises 20 to 60 wt% of olefins, 5 to 30 wt% of aromatic hydrocarbons, and 15 to 40 wt% of naphtha-range hydrocarbons.

9. In paragraph 1, A method for producing high value-added chemicals from waste plastic, wherein the oil-containing stream contains 100 to 7000 ppm of nitrogen components, 10 to 3000 ppm of sulfur components, and 1 to 5000 ppm of halogen components.

10. In paragraph 1, A method for producing high value-added chemicals from waste plastic, further comprising the step of contacting the oil-containing stream with at least one adsorbent selected from activated carbon, ion exchange resin, silica gel, clay, zeolite, molecular sieve, activated aluminum oxide, and layered double hydroxide.

11. In paragraph 1, A method for producing high value-added chemicals from waste plastic, wherein step b) is performed in a circulating fluidized bed reactor including a reactor, a stripper, and a regenerator.

12. In paragraph 1, A method for producing a high value-added chemical from waste plastic, wherein the high value-added chemical is ethylene + propylene or C2-C4 olefin or C2-C4 olefin + BTXs.

13. In paragraph 12, A method for producing high value-added chemicals from waste plastic, wherein the yield of ethylene + propylene is 40% to 50%, the yield of C2-C4 olefins is 40% to 60%, or the yield of C2-C4 olefins + BTXs is 50% to 80%, based on 100 wt% of the above oil-containing stream.

14. In paragraph 1, A method for producing a high value-added chemical substance from waste plastic, wherein the above reaction is performed at a reaction temperature of 590 to 720°C.

15. In paragraph 1, The above reaction has a weight hourly space velocity (WHSV) defined as the ratio of the mass flow rate of the oil-containing stream to the mass of the catalyst of 10 h -1 Within 20 h -1 A method for producing high value-added chemicals from waste plastics, which is performed by .

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