Method for producing olefin-containing composition and catalyst for producing olefin-containing composition

Abstract

Provided is a method for producing an olefin-containing composition, the method comprising a step for producing an olefin-containing composition containing an olefin having 2 to 5 carbon atoms by decomposing a plastic in the presence of zeolite, wherein the zeolite is an MFI-type zeolite containing Rb+.

Description

Method for producing olefin-containing composition and catalyst for producing olefin-containing composition

[0001] The present disclosure relates to a method for producing an olefin-containing composition and a catalyst for producing an olefin-containing composition.

[0002] Conventionally, waste plastics have been disposed of by landfilling, dumping in the ocean, or incineration, but it is becoming increasingly difficult to secure landfill sites, and ocean dumping poses environmental problems because plastics do not decompose. Furthermore, while incineration can be used to generate heat, the carbon dioxide emissions contribute to global warming.

[0003] Therefore, in recent years, with the growing awareness of environmental issues, there has been a need for recycling, such as reusing and regenerating waste plastics, and research and development into this area has been actively carried out. Furthermore, since most plastics are produced using fossil fuels, there is a strong demand for the development of recycling methods from the perspective of effective resource utilization.

[0004] Among plastic materials, hydrocarbon-based plastic materials such as polyethylene (PE), polypropylene (PP), and polystyrene (PS) are widely used in beverage and food containers, packaging materials, molded products, films, and other applications due to their excellent properties, including heat resistance, weather resistance, mechanical strength, transparency, chemical resistance, and gas barrier properties. Therefore, these hydrocarbon-based plastic materials account for the majority of waste plastic materials. Chemical recycling through oil-gasification is one method for recycling these plastic materials. In the oil-gasification process, waste plastics are converted into low-molecular-weight hydrocarbons by thermal decomposition. Many methods using solid catalysts have been investigated to improve reactivity and product selectivity.

[0005] For example, a method for producing olefins that provides an excellent yield of olefins having 2 to 3 carbon atoms and also provides an excellent ratio of olefins to paraffins contained in the catalytic cracker of 2 to 3 carbon atoms has been proposed, which includes a thermal cracking step in which a polyolefin-based plastic is heated to obtain a cracked product, and a catalytic cracking step in which the cracked product obtained in the thermal cracking step is contacted with an MFI zeolite containing 0.10% by mass to 0.30% by mass of sodium atoms to obtain an olefin-containing catalytic cracker (see Patent Document 1). Furthermore, Ga-supported zeolite (HZSM-5 and HZSM-11) catalysts have been proposed as catalysts with high aromatic yields, and NaHZSM-5, which is HZSM-5 subjected to Na ion exchange, has been proposed as a catalyst with high selectivity for lower olefins (see Non-Patent Document 1).

[0006] International Publication No. 2021 / 166854

[0007] Yoshio Uemichi and Yasuharu Kanda, "Hydrogen-Transfer Cracking of Plastic Mixtures Using Zeolite Catalysts," Catalysts, 2023, Vol. 65, No. 2, pp. 114-119

[0008] However, even when the catalysts disclosed in the prior art documents are used, the yield of useful components such as propylene relative to minor components such as paraffin components is not fully satisfactory.

[0009] An object of the present disclosure is to provide a method for producing an olefin-containing composition that has a low level of paraffin as a secondary component and an excellent yield of olefins having 2 to 5 carbon atoms.

[0010] A method for producing an olefin-containing composition according to one embodiment of the present disclosure includes a step of decomposing a plastic in the presence of a zeolite to produce an olefin-containing composition containing olefins having 2 to 5 carbon atoms, wherein the zeolite is selected from the group consisting of Rb ＋ The zeolite is characterized by being an MFI type zeolite containing

[0011] The means for solving the above problems are as follows: <1> A method comprising the steps of decomposing a plastic in the presence of a zeolite to produce an olefin-containing composition containing an olefin having 2 to 5 carbon atoms, wherein the zeolite is selected from the group consisting of Rb＋ <2> The method for producing an olefin-containing composition according to <1>, wherein the plastic is a polyolefin. <3> The method for producing an olefin-containing composition according to <1>, wherein the plastic contains at least one selected from the group consisting of polyethylene, polypropylene, and polystyrene. <4> The method for producing an olefin-containing composition according to any one of <1> to <3>, wherein the temperature at which the plastic is decomposed is 300°C or higher and 1,100°C or lower. <5> The method for producing an olefin-containing composition according to any one of <1> to <3>, wherein the temperature at which the plastic is decomposed is 300°C or higher and 1,100°C or lower. ＋ Al of MFI type zeolite containing ２ O ３ SiO ２ The molar ratio of [SiO ２ / Al ２ O ３ <6> The method for producing an olefin-containing composition according to any one of <1> to <4>, wherein Rb ＋ The BET specific surface area of ​​the MFI type zeolite containing ２ / g or more 1,000m ２ <7> The method for producing an olefin-containing composition according to any one of <1> to <5>, wherein the olefin-containing composition has a molecular weight of 1000 or less, and the olefin-containing composition has a molecular weight of 1000 or less. ＋ <8> The method for producing an olefin-containing composition according to any one of <1> to <6>, further comprising a calcination step of obtaining an MFI zeolite containing: ２ O ３ SiO ２ The molar ratio of [SiO ２ / Al ２ O ３] is y, and the number of moles of the rubidium compound is z (mmol), the ratio of yz / x satisfies 1≦yz / x≦10,000. ＋ <10> A catalyst for use in producing an olefin-containing composition containing an olefin having 2 to 5 carbon atoms, comprising: an MFI-type zeolite containing Rb ＋ <11> A catalyst for producing an olefin-containing composition, characterized by containing an MFI-type zeolite containing Rb ＋ The present invention relates to a method for using a catalyst containing an MFI type zeolite containing

[0012] According to an embodiment of the present disclosure, it is possible to provide a method for producing an olefin-containing composition that has a low level of paraffin as a secondary component and an excellent yield of olefins having 2 to 5 carbon atoms.

[0013] Fig. 1 is a functional configuration diagram of an information processing system used in Test Example 1. Fig. 2 is a flowchart of a process for training a machine learning model in the information processing system of Fig. 1. Fig. 3 is a flowchart of a process for predicting candidate zeolites containing metal cations having desired properties in the information processing system of Fig. 1.

[0014] The present disclosure will be described in detail below. Note that the embodiments of the present disclosure are not limited by the following description and can be modified as appropriate within the scope of the gist of the present disclosure. Furthermore, in this specification, unless otherwise specified, the term "to" indicating a range of numerical values ​​means that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0015] (Method for producing olefin-containing composition) A method for producing an olefin-containing composition according to one embodiment includes a step of decomposing a plastic in the presence of a zeolite to produce an olefin-containing composition containing olefins having 2 to 5 carbon atoms (hereinafter, this step may be referred to as a "decomposition step"), and may further include other steps as necessary.

[0016] <Cracking Step> The cracking step is a step of cracking a plastic in the presence of a zeolite to produce an olefin-containing composition containing an olefin having 2 to 5 carbon atoms.

[0017] The zeolite is Rb ＋ This is an MFI type zeolite containing Rb ＋ Compared with conventional MFI-type zeolites that do not contain olefins, the amount of paraffin that is a minor component is small, and an olefin-containing composition having an excellent yield of olefins having 2 to 5 carbon atoms can be produced.

[0018] The amount of zeolite used relative to the plastic in the decomposition step is not particularly limited and can be selected appropriately depending on the purpose. However, it is preferably 100 parts by mass or less, more preferably 10 to 100 parts by mass, even more preferably 13 to 28 parts by mass, and particularly preferably 15 to 25 parts by mass, relative to 100 parts by mass of the plastic. When the amount of zeolite used relative to the plastic is 10 to 100 parts by mass, the plastic can be decomposed effectively, and the yield of olefins having 2 to 5 carbon atoms and the O / P ratio of the olefin-containing composition, described below, are good. Furthermore, from the viewpoint of achieving the effects of the present disclosure with a small amount of zeolite, it is particularly preferable that the upper limit of the amount of zeolite used relative to the plastic be 30 parts by mass or less relative to 100 parts by mass of the plastic. Therefore, the amount of zeolite used relative to the plastic can also be 10 to 30 parts by mass.

[0019] <<Olefin-Containing Composition>> The olefin-containing composition contains an olefin having 2 to 5 carbon atoms, and preferably further contains an aromatic compound, and further contains other components as necessary.

[0020] —Olefins Having 2 to 5 Carbon atoms— The olefins having 2 to 5 carbon atoms preferably have a main component of at least one selected from the group consisting of alkenes and dienes, more preferably at least one selected from the group consisting of alkenes having 2 to 5 carbon atoms and dienes having 3 to 5 carbon atoms, and even more preferably alkenes having 2 to 5 carbon atoms.

[0021] An example of the olefin having two carbon atoms is ethylene.

[0022] An example of the olefin having 3 carbon atoms is propylene.

[0023] Examples of the olefin having 4 carbon atoms include 1-butene, cis-2-butene, trans-2-butene, and 2-methylpropene.

[0024] Examples of the olefin having 5 carbon atoms include 1-pentene, cis-2-pentene, trans-2-pentene, 2-methyl-1-butene, and 2-methyl-2-butene.

[0025] In the present disclosure, olefins having 2 to 5 carbon atoms may be referred to as "lower olefins."

[0026] The lower olefins are used as raw materials for polyolefins, and the polyolefins can be suitably used as raw materials in various fields such as plastic bags, plastic wrap, straws, medical devices, housings for home appliances, erasers, hoses, tires, tubes, CD cases, food trays, food containers, PET bottles, and fibers.

[0027] The content of the lower olefin in the olefin-containing composition is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 30% by mass or more and 100% by mass or less, and more preferably 35% by mass or more and 60% by mass or less.

[0028] -Aromatic Compound- The aromatic compound is not particularly limited and can be appropriately selected depending on the purpose, but preferably contains at least one selected from the group consisting of benzene, toluene, ethylbenzene, three positional isomers of xylene (p-xylene, m-xylene, and o-xylene), styrene, and cumene.

[0029] In the present disclosure, the aromatic compounds may be referred to as "useful aromatic compounds."

[0030] The useful aromatic compounds can be used as raw materials for resins, and the resins can be suitably used as raw materials in various fields such as CD cases, food trays, food containers, PET bottles, and fibers.

[0031] The content of the useful aromatics in the olefin-containing composition is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0% by mass or more and 50% by mass or less, more preferably 0.1% by mass or more and 30% by mass or less, even more preferably 1% by mass or more and 20% by mass or less, and particularly preferably 1% by mass or more and 10% by mass or less.

[0032] In the present disclosure, the lower olefins and the useful aromatics may be collectively referred to as "useful components."

[0033] --O / P Ratio-- In the present disclosure, a low content of paraffins, which are minor components, and an excellent yield of olefins having 2 to 5 carbon atoms can be evaluated by determining the ratio of the total yield (%) of olefin products having 2 to 5 carbon atoms to the total yield (%) of paraffin products having 2 to 5 carbon atoms, i.e., the ratio [total yield (%) of olefin products having 2 to 5 carbon atoms / total yield (%) of paraffin products having 2 to 5 carbon atoms] (hereinafter, sometimes referred to as "O / P ratio"). In the present disclosure, "paraffin" refers to aliphatic saturated hydrocarbons having 2 to 5 carbon atoms, and preferably refers to chain aliphatic saturated hydrocarbons having 2 to 5 carbon atoms.

[0034] The O / P ratio is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 1.0 or more, more preferably 1.5 or more. Since a higher O / P ratio is more preferable, the upper limit is not particularly limited, but is preferably 50 or less, more preferably 20 or less.

[0035] The number of moles of carbon atoms contained in the useful components and the O / P ratio can be determined by analyzing the olefin-containing composition obtained in the cracking step, specifically the gaseous products and residues, including those soluble in tetrahydrofuran (hereinafter sometimes abbreviated as "THF") (hereinafter sometimes referred to as "THF-soluble products"), using a gas chromatograph (hereinafter sometimes abbreviated as "GC") equipped with a flame ionization detector under the following analytical conditions, and quantifying each component using an internal standard method based on the ratio of the peak area of ​​each component to that of an internal standard. The internal standard is not particularly limited as long as it is stable under the analytical conditions and easily separable from the components to be analyzed; for example, at least one selected from the group consisting of cyclopentane and t-butylbenzene can be used. GC analysis of the gaseous products and THF-soluble products is performed under the analytical conditions described in the Examples.

[0036] When the decomposition step is carried out in a closed reaction vessel, the THF-soluble product is obtained by adding THF to the residue in the reaction vessel. When the decomposition step is carried out in a continuous or open reaction vessel, the gaseous product and the residue are recovered not only in the reaction vessel but also in a trap outside the reaction vessel, and therefore the THF-soluble product is obtained by adding THF to the residue in the reaction vessel, and by adding THF to the trap and the connecting member between the reaction vessel and the trap.

[0037] --Yield of Useful Components-- The yield of useful components is preferably 35% or more, and more preferably 40% or more.

[0038] The yield of useful components is calculated as the ratio of the number of moles of carbon atoms in the useful components to the number of moles of carbon atoms in the plastic using the following formula: Yield of useful components (%) = mass [g] of the useful components produced calculated by GC analysis / total mass [g] of plastic sample × 100

[0039] -Other Components- Examples of the other components in the olefin-containing composition include the zeolite, decomposition products of the plastics other than the useful components, undecomposed plastics, and materials or additives other than plastics contained in the raw materials.

[0040] The other components in the olefin-containing composition may be removed by a conventionally known method as appropriate when recycling the useful components.

[0041] The content of the other components in the olefin-containing composition is not particularly limited as long as it does not impair the effects of the embodiments of the present disclosure, and can be appropriately selected depending on the purpose.

[0042] <<Rb ＋ MFI-type zeolite containing >> The zeolite framework structure is compiled into a database by the International Zeolite Association (hereinafter sometimes abbreviated as "IZA"), and its IUPAC structure code (hereinafter sometimes abbreviated as "structure code") is defined. "MFI" is the structure code. The MFI-type zeolite is preferably ZSM-5 (Zeolite Socony Mobil-5).

[0043] The crystal system of the MFI zeolite can be identified by X-ray diffraction (XRD) analysis under the analytical conditions described in the Examples. It can also be identified by comparing the XRD pattern with either the XRD pattern described in "Collection of simulated XRD powder patterns for zeolites, Fifth revised edition (2007)" or the XRD pattern described in "Zeolite Framework Types" on the IZA Structure Committee website (http: / / www.iza-structure.org / databases / ).

[0044] -Pore Diameter- The pore diameter of the MFI type zeolite is generally 0.50 nm to 0.60 nm. For example, the pore diameter of the HSZ-800 series commercially available from Tosoh Corporation is 0.58 nm according to the catalog value.

[0045] The Rb ＋ The pore size of the MFI-type zeolite containing can be measured in accordance with ISO 15901-3:2007 "Pore size distribution and porosity of solid materials by mercury porosimetry and gas adsorption - Part 3: Analysis of micropores by gas adsorption".

[0046] - Molar ratio [SiO ２ / Al ２ O ３ ] - the Rb ＋ Al of MFI type zeolite containing ２ O ３ SiO ２ The molar ratio of [SiO ２ / Al ２ O ３The molar ratio [SiO ２ / Al ２ O ３ When the value of ] is 10 or more and 10,000 or less, the yield of olefins having 2 to 5 carbon atoms and the O / P ratio of the olefin-containing composition are good.

[0047] The molar ratio [SiO ２ / Al ２ O ３ ] is, for example, the Rb ＋ The MFI type zeolite containing the compound (II) is precisely weighed, completely dissolved in an aqueous solution containing nitric acid and hydrofluoric acid, and the volume of the sample is measured. The Si and Al contents of the sample are measured using an ICP optical emission spectrometer (e.g., PlasmaQuant PQ 9000, manufactured by Analytik Jena AG), and the molar ratio [SiO ２ / Al ２ O ３ ] = 2 × (number of moles of Si) / (number of moles of Al)

[0048] -BET specific surface area- Rb ＋ The BET specific surface area of ​​the MFI type zeolite containing ２ / g or more 1,000m ２ / g or less is preferable, and 100m ２ / g or more 250m ２ / g or less is more preferable, and 150m ２ / g or more 250m ２ / g or less is more preferable, and 200m ２ / g or more 250m ２ / g or less is particularly preferred. ２ / g or more 1,000m ２ / g or less, the yield of olefins having 2 to 5 carbon atoms and the O / P ratio of the olefin-containing composition are good, ２ / g or more 250m ２ When the olefin content is 1 / g or less, the yield of olefins having 2 to 5 carbon atoms and the O / P ratio of the olefin-containing composition are better.

[0049] The Rb ＋ The BET specific surface area of ​​the MFI type zeolite containing can be measured in accordance with ISO 9277:2010 "Determination of the specific surface area of ​​powders (solids) by gas adsorption."

[0050] -Particle size- The above Rb ＋ As an MFI type zeolite containing Rb, powdered Rb ＋ When an MFI-type zeolite containing the above is used, its 50% particle diameter D50 (median diameter) (volume average) is not particularly limited and can be appropriately selected depending on the purpose. From the viewpoints of the BET specific surface area, handleability, etc., it is preferably 1 μm or more and 500 μm or less, more preferably 2 μm or more and 350 μm or less, and even more preferably 2 μm or more and 100 μm or less.

[0051] Here, in the present disclosure, "powder-like" means at least one selected from the group consisting of primary particles, aggregates of primary particles (secondary particles), granules formed by granulating primary particles, and granules formed by granulating secondary particles.

[0052] The Rb ＋ The 50% particle size D50 (volume average) of the MFI zeolite containing the compound (I) means the median size measured with a laser diffraction particle size distribution analyzer (for example, a laser diffraction particle size distribution analyzer SALD-7100 manufactured by Shimadzu Corporation).

[0053] The Rb ＋ The particle shape of the MFI zeolite containing is not particularly limited, and examples thereof include spherical, ellipsoidal, crushed, flat, and irregular shapes. These may be used alone or in combination of two or more.

[0054] -Rb ＋ Method for producing MFI type zeolite containing Rb ＋The method for producing an MFI type zeolite containing Rb is not particularly limited and can be appropriately selected from methods known in the art. ＋ MFI type zeolite not containing Rb ＋ By treating with a source of Rb ＋ In another embodiment, for example, Rb ＋ It is also possible to produce a zeolite by incorporating

[0055] --Method for Producing MFI Zeolite-- A typical method for producing MFI zeolite includes, for example, a method of hydrothermal synthesis using a mixture (raw material composition) containing a silica source, an alumina source, and, if necessary, an organic structure-directing agent, a hydroxide-containing compound, a fluoride ion-containing compound, water, etc. After the hydrothermal synthesis, if necessary, solid-liquid separation treatment, water washing treatment, for example, drying treatment in the air at a temperature of about 50°C to 150°C to remove moisture, etc. may be carried out according to conventional methods. Furthermore, the organic structure-directing agent may be removed by calcination within a range that does not cause the zeolite framework to collapse, and in this case, the calcination temperature is preferably 500°C to 600°C.

[0056] The silica source is not particularly limited, but preferred are precipitated silica, colloidal silica, fumed silica, silica gel, sodium silicate (e.g., sodium metasilicate, sodium orthosilicate, sodium silicate No. 1, sodium silicate No. 2, sodium silicate No. 3, and sodium silicate No. 4), alkoxysilane (e.g., tetraethoxysilane (TEOS) and trimethylethoxysilane (TMEOS)), and the like, more preferably tetraethoxysilane (TEOS) and trimethylethoxysilane (TMEOS), and even more preferably tetraethoxysilane (TEOS). These may be used alone or in combination of two or more.

[0057] The alumina source is not particularly limited, but is preferably aluminum chloride, aluminum nitrate, aluminum sulfate, sodium aluminate, aluminum alkoxides such as aluminum isopropoxide, aluminum hydroxides such as boehmite, and more preferably aluminum nitrate. These may be used alone or in combination of two or more.

[0058] The organic structure-directing agent is not particularly limited, and is preferably a tetrapropylammonium compound such as tetrapropylammonium hydroxide, or a tetraethylammonium compound such as tetraethylammonium hydroxide. The molar ratio of the organic structure-directing agent to the silica source is preferably 0.01 or more and 0.60 or less, more preferably 0.03 or more and 0.40 or less, and even more preferably 0.05 or more and 0.35 or less.

[0059] The hydroxide-containing compound or fluoride ion-containing compound is added to promote the crystallization of zeolite, and the hydroxide-containing compound is widely used because it is inexpensive and easy to handle. There are no particular restrictions on the hydroxide-containing compound as long as it is alkaline in aqueous solution.

[0060] For example, the organic structure-directing agent can also serve as the hydroxide-containing compound, in which case hydroxide is used as the tetrapropylammonium compound or tetraethylammonium compound described above. This method allows for the production of proton-type zeolite without incorporating alkali metals into the zeolite.

[0061] On the other hand, alkali metal ions may be present in the zeolite. Alternatively, if alkali metal ions are to be actively introduced into the zeolite, an alkali metal or alkaline earth metal hydroxide, preferably an alkali metal hydroxide, is added as the hydroxide-containing compound in addition to the organic structure-directing agent. Examples of organic structure-directing agents used in this case include tetrapropylammonium bromide and tetraethylammonium bromide. Examples of alkali metal hydroxides include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, and cesium hydroxide.

[0062] Rb in advance ＋ The Rb used in producing an MFI zeolite by incorporating ＋ The source is not particularly limited, and examples thereof include rubidium compounds. Specifically, rubidium hydroxide is used as the hydroxide to produce Rb ＋ It can also serve as a source of ＋ As a method for introducing alkali metal ions such as Rb, an alkali metal compound other than hydroxide can be added. In this case, a hydroxide-containing compound or a fluoride ion-containing compound is added separately to promote the crystallization of the zeolite. ＋ When alkali metal ions are incorporated using a Rb source or other alkali metal compounds, the alkali metal compounds are often in excess, so washing with water is carried out after hydrothermal synthesis to remove the excess alkali metal ions. ＋ The source is preferably added before the hydrothermal synthesis.

[0063] The water used in the hydrothermal synthesis is not particularly limited, and examples thereof include industrial water, tap water, distilled water, deionized water, pure water, RO water (water treated with a reverse osmosis membrane), and ultrapure water. These may be used alone or in combination of two or more.

[0064] The hydrothermal synthesis is usually carried out in a reaction vessel. The reaction vessel used in this hydrothermal synthesis can be any known sealed pressure-resistant vessel that can be used for hydrothermal synthesis, and the type is not particularly limited. For example, a sealed heat-resistant and pressure-resistant vessel such as an autoclave equipped with a stirrer, a heat source, a pressure gauge, and a safety valve is preferably used. Note that, although the crystallization of the zeolite may be carried out while the mixture is left standing, it is preferable to carry out the crystallization while the mixture is stirred and mixed in order to improve the uniformity of the resulting zeolite.

[0065] The treatment temperature (reaction temperature) of the hydrothermal synthesis is not particularly limited and can be appropriately selected from the viewpoints of the crystallinity of the zeolite to be obtained, economic efficiency, etc., but is preferably 100°C or higher and 200°C or lower, more preferably 120°C or higher and 190°C or lower, and even more preferably 150°C or higher and 180°C or lower.

[0066] The treatment time (reaction time) for the hydrothermal synthesis is not particularly limited as long as it can crystallize, and can be appropriately selected from the viewpoints of the crystallinity of the resulting zeolite, economic efficiency, etc., but is preferably from 1 hour to 20 days, more preferably from 4 hours to 15 days, and even more preferably from 12 hours to 11 days.

[0067] The treatment pressure for the hydrothermal synthesis is not particularly limited, and the autogenous pressure generated when the mixture introduced into the reaction vessel is heated to the above-mentioned temperature range is sufficient. At this time, an inert gas such as nitrogen gas or argon gas may be introduced into the vessel, if necessary.

[0068] The zeolite contains ammonium ions (NH ４ ＋ ) and protons (H ＋ ) and the nonmetallic cations. ＋ Source Rb ＋ The method for carrying out the ion exchange with the cation exchange agent is not particularly limited, and can be carried out by a conventional method.

[0069] --MFI type zeolite as raw material, Rb ＋ Method for producing MFI zeolite containing Rb of the present disclosure ＋ The method for producing the contained MFI zeolite includes a mixing step and a calcination step, and preferably further includes a stirring step and an evaporation / drying step, and further includes other steps as necessary.

[0070] ---Mixing Step--- The mixing step is a step of obtaining a mixed liquid by mixing an MFI type zeolite (hereinafter, sometimes referred to as "raw zeolite") with a liquid containing a rubidium compound.

[0071] By carrying out the mixing step, for example, the cation (Rb＋ ) can be ionically bonded.

[0072] The rubidium compound is not particularly limited, and examples thereof include rubidium hydroxide, rubidium nitrate, rubidium chloride, and rubidium carbonate. These may be used alone or in combination of two or more. Among these, rubidium nitrate is preferred as the rubidium compound because of its excellent solubility.

[0073] The raw material zeolite in the mixing step may be an acidic zeolite or a basic zeolite, and among these, it is preferable to use an acidic zeolite having Bronsted acid sites as the raw material zeolite, since exchange with cations proceeds well when a liquid containing a rubidium compound is used.

[0074] The raw material zeolite used in the mixing step is not particularly limited, and may be suitably synthesized or a commercially available product.

[0075] The method for synthesizing the raw material zeolite is not particularly limited and can be appropriately selected from known methods. For example, there is a method in which an aqueous aluminum nitrate solution is added to tetraalkoxysilane to hydrolyze the zeolite, and the resulting alcohol is then distilled off, followed by hydrothermal synthesis and calcination.

[0076] The solvent for the liquid containing the rubidium compound is not particularly limited, but is preferably one that can dissolve the rubidium compound, is relatively easily removable in the baking step described below, and does not decompose, and a highly polar solvent is more preferred. Examples of such solvents include water, methanol, ethanol, acetonitrile, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, and hexamethylphosphoric triamide. These may be used alone or in combination of two or more. Among these solvents, at least one selected from the group consisting of water, methanol, and ethanol is preferred because it has a relatively low boiling point and can be easily removed, and water is particularly preferred because of its low cost.

[0077] The concentration of the rubidium compound contained in the liquid containing the rubidium compound is not particularly limited and can be appropriately selected depending on the purpose, but from the viewpoint of reducing solvent costs, it is preferably from 0.01 mol / L to 10 mol / L, more preferably from 0.05 mol / L to 2.5 mol / L, and still more preferably from 0.05 mol / L to 0.5 mol / L. When the concentration of the rubidium compound is from 0.01 mol / L to 10 mol / L, a uniform mixture of the raw zeolite and a solution in which the rubidium compound is dissolved in the solvent can be obtained, and this is also advantageous in terms of cost.

[0078] The amount of rubidium compound used in the liquid containing the rubidium compound is determined based on the acidity of the raw zeolite (i.e., the cation (Rb ＋ cation (Rb) in the rubidium compound relative to the amount of substance at which the ＋ ) and the valence of the cation (Rb ＋ ) and the amount of substance [Rb in the rubidium compound contained in the liquid containing rubidium compound] ＋ When two or more rubidium compounds are used, the amount of the cation (Rb ＋ The valence of the cation (Rb ＋ ) in the rubidium compound, and ＋ The amount of substance of the cation (Rb ＋ ) is the sum of the amounts of substance.

[0079] The ratio [Rb ＋ The ratio [(valence × amount of substance) / acid amount of raw zeolite] is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 40 or more and 4,000 or less, and more preferably 200 or more and 600 or less. ＋When the ratio of (valence × amount of substance) / acid amount of raw zeolite is 40 or more, the cations (Rb ＋ ) can be sufficiently provided. ＋ When the ratio (valence number x amount of substance) / acid amount of raw zeolite) is 4,000 or less, it is advantageous in terms of cost.

[0080] The amount of acid in the raw zeolite can be determined, for example, by measuring the amount of base adsorbed on the raw zeolite by temperature programmed desorption (TPD) using an appropriate base (e.g., ammonia).

[0081] The method for mixing the raw material zeolite with a liquid containing a rubidium compound to prepare a mixed liquid is not particularly limited and can be appropriately selected depending on the purpose. For example, a method of immersing the raw material zeolite in a solution in which a rubidium compound is dissolved in a solvent can be mentioned.

[0082] The cation contained in the raw material zeolite is not particularly limited, but may be H ＋ The MFI type zeolite contains Rb ＋ This is preferred in terms of the efficiency of substitution.

[0083] The Rb ＋ As a raw material for MFI type zeolite containing H ＋ When using an MFI type zeolite containing ＋ The acid amount of the MFI type zeolite containing H is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 0.01 mmol / g or more and 2.5 mmol / g or less, more preferably 0.01 mmol / g or more and 2.0 mmol / g or less, and even more preferably 0.01 mmol / g or more and 0.1 mmol / g or less. ＋ When the amount of MFI-type zeolite acid containing Rb is 0.01 mmol / g or more and 2.5 mmol / g or less, the yield of olefins having 2 to 5 carbon atoms and the O / P ratio of the olefin-containing composition are good. ＋ A zeolite of MFI type containing

[0084] The H ＋ The acid amount of the MFI type zeolite containing the above can be measured by the ammonia temperature programmed desorption method (hereinafter sometimes abbreviated as "TPD").

[0085] In the mixing step, the mass of the MFI zeolite is defined as x (g), and the Al content of the MFI zeolite is defined as ２ O ３ SiO ２ The molar ratio of [SiO ２ / Al ２ O ３ When the molar ratio of the rubidium compound is y and the number of moles of the rubidium compound is z (mmol), the range obtained by dividing the value obtained by multiplying y and z by x (the range of yz / x (mmol / g)) is not particularly limited and can be appropriately selected depending on the purpose, but preferably satisfies 1≦yz / x≦10,000, more preferably satisfies 2,000≦yz / x≦8,000, and further preferably satisfies 4,000<yz / x≦6,000. By satisfying 1≦yz / x≦10,000, the MFI zeolite can be made to have a high concentration of Rb ＋ By containing the olefin-containing composition, the effect of improving the O / P ratio of the olefin-containing composition can be sufficiently obtained, and it is advantageous in terms of the labor required for preparing the zeolite and the raw material cost.

[0086] ---Stirring Step--- The stirring step is a step of stirring the mixture of the raw zeolite and the liquid containing the rubidium compound to obtain a solution-treated zeolite.

[0087] The method for stirring the mixture is not particularly limited, and any known method can be used.

[0088] The stirring time for the mixed solution is not particularly limited and can be determined appropriately depending on the concentration of the rubidium compound contained in the rubidium compound-containing liquid, but is preferably 0.5 to 48 hours, more preferably 1 to 24 hours, and even more preferably 6 to 15 hours at room temperature under an atmospheric atmosphere. A stirring time of 0.5 hours or more allows the cations contained in the rubidium compound to be sufficiently added to the raw zeolite. Furthermore, a stirring time of 48 hours or less prevents contamination by substances contained in the air and non-uniform addition of cations due to changes in the concentration of the mixed solution.

[0089] The solution-treated zeolite obtained by carrying out the stirring step is preferably filtered and washed, for example, by gravity filtration, suction filtration, etc. The solution-treated zeolite can be washed, for example, by passing the filtered solution-treated zeolite through the solvent used in the solution obtained by dissolving a rubidium compound in a solvent.

[0090] ---Evaporation and Drying Step--- The evaporation and drying step is a step in which the zeolite after the solution treatment is evaporated to dryness without being filtered. By including the evaporation and drying step, cation exchange can be further promoted.

[0091] The evaporation-to-dryness method is not particularly limited and can be appropriately selected depending on the type of solvent contained in the mixed solution. When the solvent is water, for example, the method includes leaving the mixture at room temperature in an atmospheric environment for an appropriate period of time. In this case, the leaving time is not particularly limited as long as the solvent can be removed, but is preferably 2 to 14 days, more preferably 3 to 12 days, and even more preferably 4 to 6 days.

[0092] The evaporation-drying step may be carried out by heating for an appropriate period of time in an air atmosphere using an oven set at a temperature above room temperature and below the boiling point of the solvent, where the temperature does not cause bumping of the solvent. By using this method, the time required for the evaporation-drying step to be completed can be shortened. The heating time using the oven may be adjusted appropriately depending on the heating temperature. For example, when the solvent is water, the step may be carried out at a temperature of about 80°C for 5 to 10 hours, or at a temperature of about 50°C for 40 to 60 hours.

[0093] Furthermore, the solution-treated zeolite collected by evaporation to dryness is preferably washed with the solvent used in preparing the rubidium compound solution to remove excess rubidium compound that is thought to have precipitated on the surface, before proceeding to the calcination step.

[0094] --- Calcination Step --- The calcination step is a step of calcining the zeolite obtained after the mixing step, the stirring step, or the evaporation drying step.

[0095] When an acidic zeolite is used as the raw zeolite, the calcination step can further promote the addition of cations by volatilizing protons on acid sites remaining on the raw zeolite even after the mixing step and the stirring step, and nitrate ions derived from the rubidium compound, as water and nitrogen dioxide. In addition, the solvent remaining even after the filtration and evaporation drying steps can be almost completely removed.

[0096] The conditions and temperature for calcining the solution-treated zeolite in the calcination step are not particularly limited, but are preferably 300°C to 600°C in an air atmosphere, more preferably 450°C to 550°C in an air atmosphere.

[0097] The calcination time of the zeolite after the solution treatment in the calcination step is not particularly limited, but is preferably 1 hour to 20 hours, more preferably 6 hours to 15 hours.

[0098] In addition, the Rb ＋The pore size of the MFI-type zeolite containing Rb can be controlled by changing the conditions of the mixing step and the stirring step. It is estimated that the smaller the BET specific surface area, the smaller the pore size of the produced zeolite. The ratio of the valence of the cation in the rubidium compound contained in the solution to the amount of substance (the amount of acid in the raw zeolite) at which the cation in the raw zeolite can be added, and the valence of the cation in the rubidium compound (Rb ＋ ) and the amount of substance [Rb in the rubidium compound contained in the liquid containing rubidium compound] ＋ By varying at least one condition selected from the group consisting of (valence × amount of substance) / acid amount of raw zeolite), the concentration of the rubidium compound contained in a solution obtained by dissolving the rubidium compound in a solvent, and the stirring time of the mixed solution, zeolites with different BET specific surface areas can be produced.

[0099] <<Plastic>> The plastic is not particularly limited and can be appropriately selected depending on the purpose. However, from the viewpoint of reducing the environmental load, it preferably contains waste plastic, more preferably contains polyolefin, and even more preferably contains at least one selected from the group consisting of polyethylene (PE), polypropylene (PP), and polystyrene (PS), which are widely used in beverage and food containers, packaging materials, molded products, films, etc.

[0100] In addition to the above-mentioned plastics, the plastic may include other plastics such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polycarbonate (PC), polyvinyl chloride, polyvinylidene chloride, chlorinated polyethylene, polyamide, polyurethane, acrylonitrile-butadiene-styrene copolymer, and polymethyl methacrylate.

[0101] When the plastic is waste plastic, the composition ratio is preferably 20% to 40% by mass of PE, 20% to 40% by mass of PP, and 10% to 30% by mass of PS.

[0102] The content of the other plastics in the plastics is not particularly limited and can be selected appropriately depending on the type of waste plastic, etc., but from the viewpoint of the yield of olefins having 2 to 5 carbon atoms and the O / P ratio of the olefin-containing composition, the content is preferably 50 mass% or less of the total mass of the plastics, more preferably 45 mass% or less, and even more preferably 40 mass% or less.

[0103] The plastic may be a plastic composition further containing a material other than plastic or an additive. When the plastic composition is a waste plastic composition, examples of the material other than plastic include paper and metal.

[0104] There are no particular restrictions on the content of materials other than the plastics or additives in the plastic composition.

[0105] The decomposition step is preferably carried out under heating, since this improves the decomposition efficiency.

[0106] The reactor in which the decomposition step is carried out is not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include a batch reactor, a fixed bed reactor, and a fluidized bed reactor.

[0107] The temperature at which the decomposition step is carried out (hereinafter may be referred to as "decomposition temperature") is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 300° C. or higher and 1,100° C. or lower, more preferably 300° C. or higher and 600° C. or lower. When the decomposition temperature is 300° C. or higher and 1,100° C. or lower, the zeolite is easily activated, and the yield of olefins having 2 to 5 carbon atoms and the O / P ratio of the olefin-containing composition are good.

[0108] The time for decomposition at the decomposition temperature (hereinafter sometimes referred to as "decomposition time") is not particularly limited and can be appropriately selected depending on the reaction system, etc. For example, when the decomposition is performed using a sealed batch reactor, the decomposition time is preferably 1 hour or more and 20 hours or less, and more preferably 5 hours or more and 10 hours or less. When the decomposition time is 1 hour or more, the plastic can be decomposed favorably, and the yield of olefins having 2 to 5 carbon atoms and the O / P ratio of the olefin-containing composition are good. Furthermore, when the decomposition time is 20 hours or less, it is efficient.

[0109] The atmosphere in which the decomposition is carried out is not particularly limited and can be appropriately selected depending on the purpose, but it is preferable to carry out the decomposition in the presence of an inert gas.

[0110] The inert gas is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include nitrogen gas and argon gas. These may be used alone or in combination of two or more.

[0111] In order to completely fluidize the plastics, some of the plastics may be vaporized in the decomposition process. Furthermore, in the case of industrial waste, relatively homogeneous waste plastic materials consisting of specific plastic components and having a molecular weight distribution within a certain range may be obtained. In such cases, it is preferable to set the treatment conditions for the decomposition process according to the type and molecular weight of the plastic components that make up the waste plastic material. Separating inorganic substances from waste plastic materials, which are general waste, may be done using a laboratory-scale separation device, but it can also be carried out on an industrial level in various plants, such as oil refineries.

[0112] <Other Steps> The other steps in the production method of the olefin-containing composition are not particularly limited and can be appropriately selected depending on the purpose. Examples thereof include a pretreatment step for the plastic and a recovery step of the volatile components obtained in the decomposition step. ＋ The method may include a mixing step, a stirring step, and a calcination step to produce an MFI type zeolite containing

[0113] <<Pretreatment Step>> The pretreatment step is a step of pretreating the plastic before subjecting it to the decomposition step. In the pretreatment step, the plastic is put into a form or state that is easy to decompose, thereby enabling the plastic to be decomposed more efficiently.

[0114] Examples of the pretreatment include crushing the plastic, pelletizing (chipping) the crushed plastic, and melting the plastic.

[0115] The melt processing of the plastic is preferably carried out in the absence of zeolite at a temperature below 300°C.

[0116] The pulverized plastic material is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include powder and flake forms.

[0117] The method for obtaining the pulverized plastic is not particularly limited and can be appropriately selected from conventionally known methods, such as a method in which the plastic is pulverized using a pulverizer to obtain powder or flakes.

[0118] Furthermore, the method for pelletizing the pulverized material (chips) is not particularly limited and can be appropriately selected from conventionally known methods, such as a method in which the pulverized material is melt-extruded and then the strand-like molten extruded material is cut to obtain chipped raw material.

[0119] The plastics can also be supplied to the decomposition step in a molten state. The method for melting the plastics is not particularly limited and can be appropriately selected from conventionally known methods, such as a method in which the plastics are continuously supplied to the decomposition step using a melt extruder.

[0120] <<Volatile Component Recovery Step>> The volatile component recovery step is a step of recovering the volatile components obtained in the decomposition step.

[0121] The inclusion of the volatile component recovery step is advantageous in that, if volatile components are generated in the decomposition step, they can be recovered or removed depending on their usefulness. For example, if the plastic contains polystyrene, the styrene monomer generated in the decomposition step can be vaporized and recovered. The recovered styrene monomer can be advantageously reused for the production of polystyrene, etc. Furthermore, if the plastic material contains chlorine-containing plastics such as polyvinyl chloride and polyvinylidene chloride, it is preferable to vaporize and remove hydrogen chloride generated when the chlorine-containing plastic is heated in the decomposition step. Furthermore, separately from the decomposition step, the plastic can be heated at a low temperature in advance to vaporize the hydrogen chloride before being subjected to the decomposition step. In this case, the low-temperature heating temperature is preferably 100°C or higher but lower than 300°C. This allows the chlorine content of the fluidized olefin-containing composition to be reduced after the plastic is fluidized.

[0122] The method for recovering the volatile components is not particularly limited, and can be appropriately selected from conventionally known methods.

[0123] By the above-described method for producing an olefin-containing composition, it is possible to obtain a raw material suitable for chemical recycling, which has a low content of paraffin as a secondary component and an excellent yield of olefins having 2 to 5 carbon atoms.

[0124] (Catalyst for producing an olefin-containing composition) In one embodiment of the present disclosure, the catalyst for producing an olefin-containing composition is a catalyst used for producing an olefin-containing composition containing an olefin having 2 to 5 carbon atoms, and the catalyst comprises Rb ＋ The composition contains an MFI type zeolite containing the above-mentioned compound, and further contains other components as necessary.

[0125] The raw material of the olefin-containing composition can be plastic.

[0126] <Rb ＋ MFI-type zeolite containing Rb ＋ The MFI type zeolite containing the above is as described in the section (Method for producing an olefin-containing composition).

[0127] In the catalyst for producing an olefin-containing composition, ＋ The content of the MFI type zeolite containing Rb is not particularly limited as long as it does not impair the effects of the present embodiment, and can be appropriately selected depending on the purpose. ＋ The MFI type zeolite itself containing Rb ＋ The content of the MFI type zeolite containing the above may be 100% by mass.

[0128] <Other Components> The other components in the catalyst for producing an olefin-containing composition are not particularly limited, and examples thereof include a pH adjuster, an antiseptic and antifungal agent, a binder, and a granulation aid.

[0129] The content of the other components in the catalyst for producing an olefin-containing composition is not particularly limited as long as it does not impair the effects of the embodiment of the present disclosure, and can be appropriately selected depending on the purpose.

[0130] The catalyst for producing the olefin-containing composition is a catalyst, i.e., the Rb ＋ The MFI type zeolite containing Rb is used for producing an olefin-containing composition containing an olefin having 2 to 5 carbon atoms. ＋ Also included within the scope of this disclosure are methods of using catalysts containing MFI-type zeolites containing:

[0131] Hereinafter, embodiments of the present disclosure will be specifically described with reference to Test Examples, Reference Production Examples, Production Examples, Comparative Production Examples, Examples, and Comparative Examples, but the embodiments of the present disclosure are in no way limited to these Test Examples, Reference Production Examples, Production Examples, Comparative Production Examples, Examples, and Comparative Examples. In the following description, "%" indicates "% by mass" unless otherwise specified.

[0132] (Test Example 1: Prediction Test) Using an information processing system constructed using zeolite parameters, metal cation parameters, and ion-exchange anion parameters as explanatory variables and the reaction yield of organic compounds as the target variable, the relationship between the yield of useful components obtained by decomposition of plastics when zeolite containing metal cations is used as a catalyst and the O / P ratio was predicted.

[0133] Specifically, using an information processing system 1 having the functional configuration shown in FIG. 1, the learning process of the machine learning model was performed according to the procedure shown in FIG. 2, and the relationship between the yield of useful components obtained by decomposing plastics and the O / P ratio when zeolite containing metal cations was used as a catalyst was predicted according to the procedure shown in FIG. 3.

[0134] The information processing system 1 includes a design support device 10, a learning device 11, and a user terminal 12. The user terminal 12 is an information processing terminal operated by an operator. The design support device 10 is an information processing device such as a PC that supports more efficient design of zeolites containing metal cations with desired properties. The design support device 10 generates comprehensive combinations of zeolite parameters, metal cation parameters, and ion-exchange anion parameters, predicts reaction yields of organic compounds corresponding to the comprehensive combinations using a trained machine learning model, and outputs candidates for zeolites containing metal cations with desired properties. The learning device 11 is a device that trains a machine learning model to learn the correspondence between information on zeolite parameters, metal cation parameters, and ion-exchange anion parameters and reaction yields of organic compounds.

[0135] 2, the training dataset acquisition unit 52 of the learning device 11 acquired a training dataset to be used for training the machine learning model. The training dataset was a training dataset that represented the correspondence between the parameters of zeolite, the parameters of metal cations, and the parameters of ion-exchange anions and the reaction yield of organic compounds.

[0136] Next, by the process of step S12 shown in FIG. 2, the learning data set is analyzed using a specific parameter table to determine the parameters of the zeolite (item "crystal system"), the parameters of the metal cations (items "cation species", "cation ion crystal radius", "cation electronegativity", and "cation charge"), and the parameters of the ion-exchanged anions (item "ion-exchanged anion: NO") ３ － " and "ion exchange anion: OH － ") and the reaction yields of organic compounds (items "ethylene yield," "propylene yield," "total yield of C4 olefins and C5 olefins," "yield of useful aromatics," and "O / P ratio").

[0137] Next, in step S14 shown in FIG. 2, the learning unit 54 trained the machine learning model to learn the correspondence between the zeolite parameters, the metal cation parameters, and the ion-exchange anion parameters and the reaction yield of the organic compound based on the training data set after parameter conversion.

[0138] Next, the information processing system 1 predicted candidate zeolites containing metal cations that could provide good yields of useful components and good O / P ratios, using the procedure shown in FIG.

[0139] In step S20, the design support device 10 acquires the trained machine learning model trained by the learning device 11.

[0140] In step S22, the search range receiving unit 26 received an input of a search range for zeolites containing metal cations.

[0141] In step S24, the parameter generation unit 28 generated comprehensive combinations of zeolite parameters, metal cation parameters, and ion-exchange anion parameters within the search range for zeolites containing the metal cations input in step S22.

[0142] In step S26, the parameter generating unit 28 converted the parameters of the items that needed to be converted into parameters using a specific parameter table for each of the comprehensive combinations of the zeolite parameters, the metal cation parameters, and the ion-exchange anion parameters generated in step S24. Note that the BET specific surface area of ​​the zeolite and the molar ratio [SiO ２ / Al ２ O ３ ] is not uniquely determined by the zeolite framework, so a separate value was entered.

[0143] In step S28, the prediction unit 30 inputs the comprehensive combinations of the zeolite parameters, metal cation parameters, and ion-exchange anion parameters generated by the parameter generation unit 28 into the trained machine learning model, thereby predicting the reaction yields of the organic compounds (items "ethylene yield," "propylene yield," "total yield of C4 olefins and C5 olefins," "useful aromatics yield," and "O / P ratio").

[0144] In step S30, the candidate output unit 32 tallies the reaction yields of organic compounds corresponding to the exhaustive combinations predicted by the prediction unit 30, and sorts them in descending order of yield for each item.

[0145] In step S32 , the candidate output unit 32 outputs data on candidate zeolites containing metal cations based on the reaction yields of organic compounds corresponding to the exhaustive combinations predicted by the prediction unit 30 .

[0146] As a result of the prediction test using the information processing system 1, it was found that the zeolite that can give good results in useful component yield and O / P ratio is one having an MFI type crystal system and Rb cations. ＋ , Sr ２＋ , and Cs ＋ It was predicted that this would be the case.

[0147] Based on the above prediction results, more detailed predictions were made for the combinations of zeolite crystal systems, cations, and anions shown in Table 1 below. The results are shown in Table 1 below.

[0148]

[0149] Reference Production Example 1 <Synthesis of Zeolite A> 55 g (0.26 mol) of tetraethoxysilane was weighed into a 200 mL three-neck flask equipped with a stirrer, a condenser, and a dropping funnel. Separately, 0.132 g of aluminum nitrate nonahydrate was dissolved in 10 g of pure water to prepare an aluminum nitrate aqueous solution. While stirring the tetraethoxysilane in the three-neck flask at room temperature (20°C ± 5°C), the entire amount of the aluminum nitrate aqueous solution was added and mixed to prepare a mixture. Subsequently, while stirring the mixture at room temperature, 85.06 g (0.085 mol) of a 1 mol / L tetrapropylammonium hydroxide aqueous solution was added dropwise from the dropping funnel over 1 hour. The reactor was then heated in an oil bath set to 100°C, and the mixture was stirred for 1 hour to hydrolyze the tetraethoxysilane. Next, the condenser of the three-neck flask was replaced with a distillation apparatus, and the reactor was heated in an oil bath set to 130°C. The ethanol produced by the hydrolysis was distilled off over 1.5 hours. During the distillation of ethanol, pure water was added twice at 5 mL each time, ultimately yielding approximately 70 mL of mixed liquid slurry. The entire amount of the resulting mixed liquid slurry was placed in an autoclave equipped with a Teflon (registered trademark) inner cylindrical container, and hydrothermal synthesis was performed at 180°C for 11 days. After cooling to room temperature, the slurry was centrifuged to separate the solid from the liquid. The resulting solid was washed twice by adding pure water, stirring, and centrifuging. The resulting solid was dried at 80°C for 1 day. The resulting dried solid was calcined in air at 550°C for 6 hours to decompose and remove organic matter, yielding MFI zeolite (hereinafter sometimes referred to as "zeolite a").

[0150] (Production Example 1) <Treatment Step> Rubidium nitrate (RbNO ３ Pure water was added to 1.5 g (by mass) (10.20 mmol) of zeolite a (purity: 95.0% or higher, manufactured by Kanto Chemical Co., Inc.) to completely dissolve it, thereby preparing a 0.20 mol / L aqueous rubidium nitrate solution. 5 g of zeolite a obtained in Reference Production Example 1 and the entire amount of the aqueous rubidium nitrate solution were mixed in a glass container and stirred at room temperature in an air atmosphere for 12 hours to obtain a reaction product.

[0151] <Caking Step> After the treatment step, the reaction product was left to stand at room temperature in an air atmosphere for 5 days, and evaporated to dryness to obtain a solidified product. The obtained solidified product was washed with water, transferred to a porcelain crucible, and calcined in an electric furnace set at 500°C in an air atmosphere for 8 hours to obtain a solid catalyst of Production Example 1.

[0152] (Production Example 2) In Production Example 1, rubidium nitrate (RbNO ３ 1.5 g (by mass) (10.20 mmol) of rubidium nitrate (RbNO , purity: 95.0% or more, manufactured by Kanto Chemical Co., Inc.) was added to pure water and completely dissolved to prepare a 0.20 mol / L aqueous rubidium nitrate solution. ３ A solid catalyst of Production Example 2 was obtained by performing the zeolite treatment step and the calcination step in the same manner as in Production Example 1, except that 2.0 g (by mass) (13.90 mmol) of sodium nitrate (purity: 95.0% or more, manufactured by Kanto Chemical Co., Inc.) was added to pure water to completely dissolve it, thereby preparing a 0.28 mol / L aqueous sodium nitrate solution.

[0153] (Production Example 3) In Production Example 1, rubidium nitrate (RbNO ３ 1.5 g (by mass) (10.20 mmol) of rubidium nitrate (RbNO , purity: 95.0% or more, manufactured by Kanto Chemical Co., Inc.) was added to pure water and completely dissolved to prepare a 0.20 mol / L aqueous rubidium nitrate solution. ３ A solid catalyst of Production Example 3 was obtained by performing the zeolite treatment step and the calcination step in the same manner as in Production Example 1, except that 2.7 g (by mass) (18.60 mmol) of sodium nitrate (purity: 95.0% or more, manufactured by Kanto Chemical Co., Inc.) was added to pure water to completely dissolve it, thereby preparing a 0.37 mol / L aqueous sodium nitrate solution.

[0154] Comparative Production Example 1 A solid catalyst of Comparative Production Example 1 was obtained by carrying out the zeolite synthesis step and the calcination step in the same manner as in Production Example 1, except that the treatment steps in Production Example 1 were changed as follows.

[0155] <Treatment process> Sodium nitrate (NaNO ３0.84 g (mass) (9.88 mmol) of zeolite a (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was completely dissolved in pure water to prepare a 0.20 mol / L aqueous sodium nitrate solution. 5 g of zeolite a obtained in Reference Production Example 1 and the entire amount of the aqueous sodium nitrate solution were mixed in a glass container and stirred at room temperature in an air atmosphere for 12 hours to obtain a reaction product.

[0156] Comparative Production Example 2 A solid catalyst of Comparative Production Example 2 was obtained by carrying out the zeolite synthesis step and the calcination step in the same manner as in Production Example 1, except that the treatment steps in Production Example 1 were changed as follows.

[0157] <Treatment process> Potassium nitrate (KNO ３ Pure water was added to 1.0 g (by mass) (9.89 mmol) of zeolite a (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) to completely dissolve it, thereby preparing a 0.20 mol / L aqueous potassium nitrate solution. 5 g of zeolite a obtained in Reference Production Example 1 and the entire amount of the aqueous potassium nitrate solution were mixed in a glass container, and the mixture was stirred in an air atmosphere at room temperature for 12 hours to obtain a reaction product.

[0158] Comparative Production Example 3 A solid catalyst of Comparative Production Example 3 was obtained by carrying out the zeolite synthesis step and the calcination step in the same manner as in Production Example 1, except that the treatment steps in Production Example 1 were changed as follows.

[0159] <Treatment process> Cesium nitrate (CsNO ３ Pure water was added to 1.9 g (by mass) (9.75 mmol) of zeolite a (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) to completely dissolve it, thereby preparing a 0.20 mol / L aqueous cesium nitrate solution. 5 g of zeolite a obtained in Reference Production Example 1 and the entire amount of the aqueous cesium nitrate solution were mixed in a glass container, and the mixture was stirred at room temperature in an air atmosphere for 12 hours to obtain a reaction product.

[0160] Comparative Production Example 4 A solid catalyst of Comparative Production Example 4 was obtained by carrying out the zeolite synthesis step and the calcination step in the same manner as in Production Example 1, except that the treatment steps in Production Example 1 were changed as follows.

[0161] <Treatment process> Strontium nitrate (Sr(NO ３ ) ２Pure water was added to 1.0 g (by mass) (4.70 mmol) of strontium nitrate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) to completely dissolve it, thereby preparing a 0.09 mol / L aqueous strontium nitrate solution. 5 g of zeolite a obtained in Reference Production Example 1 and the entire amount of the aqueous strontium nitrate solution were mixed in a glass container, and the mixture was stirred at room temperature in an air atmosphere for 12 hours to obtain a reaction product.

[0162] Comparative Production Example 5 Titanosilicate Synthesis Step 107 g (0.514 mol) of tetraethoxysilane and 4.9 g of tetra(n-butoxy)titanium were weighed into a 500 mL three-neck flask equipped with a stirrer, condenser, and dropping funnel. Subsequently, 168.1 g (0.168 mol) of a 1 mol / L aqueous tetrapropylammonium hydroxide solution was added dropwise from the dropping funnel over 1.5 hours while stirring under ice cooling. The reactor was then heated in an oil bath set to 100°C, and the mixture was stirred for 1 hour to hydrolyze the tetraethoxysilane. The condenser of the three-neck flask was then replaced with a distillation apparatus, and the reactor was heated in an oil bath set to 130°C. The ethanol produced by the hydrolysis was removed by distillation over 1.5 hours. During the distillation of the ethanol, pure water was added twice at 5 mL each time, ultimately yielding approximately 70 mL of a mixed liquid slurry. The entire amount of the resulting mixed liquid slurry was placed in an autoclave equipped with a Teflon (registered trademark) inner cylindrical container, and hydrothermal synthesis was carried out at 180°C for 6 days. After cooling to room temperature, the slurry was centrifuged to separate the solid and liquid. The resulting solid was washed twice by adding pure water, stirring, and centrifuging. The resulting solid was dried at 80°C for 1 day. The resulting dried solid was calcined in air at 550°C for 6 hours to decompose and remove organic matter, yielding titanosilicate (hereinafter, sometimes referred to as "TS-1"). This TS-1 was used as the solid catalyst of Comparative Production Example 5.

[0163] Comparative Production Example 6 A solid catalyst of Comparative Production Example 6 was obtained by carrying out the zeolite synthesis step and the calcination step in the same manner as in Production Example 1, except that the treatment steps in Production Example 1 were changed as follows.

[0164] <Treatment process> Rubidium nitrate (RbNO ３0.92 g (mass) (6.24 mmol) of rubidium nitrate (manufactured by Kanto Chemical Co., Inc.) was dissolved completely in pure water to prepare a 0.12 mol / L aqueous solution of rubidium nitrate. In a glass container, faujasite (FAU)-type zeolite (high silica zeolite HSZ-300, Type 350HUA, manufactured by Tosoh Corporation, molar ratio [SiO ２ / Al ２ O ３ ]:10) (hereinafter, sometimes referred to as "zeolite b") and the entire amount of the aqueous rubidium nitrate solution were mixed, and the mixture was stirred in an air atmosphere at room temperature for 12 hours to obtain a reaction product.

[0165] Comparative Production Example 7 In the treatment step of Comparative Production Example 1, pure water was added to 0.84 g (mass) (9.88 mmol) of sodium nitrate to completely dissolve it, and a 0.2 mol / L aqueous sodium nitrate solution was prepared. Instead, pure water was added to 0.61 g (mass) (7.20 mmol) of sodium nitrate to completely dissolve it, and a 0.14 mol / L aqueous sodium nitrate solution was prepared. Zeolite a obtained in Reference Production Example 1 was replaced with commercially available MFI-type zeolite (high silica zeolite HSZ-800, Type 840HOA, manufactured by Tosoh Corporation, molar ratio [SiO ２ / Al ２ O ３ ]: 40) (hereinafter, sometimes referred to as "zeolite c") was used. The zeolite treatment step and the calcination step were carried out in the same manner as in Comparative Production Example 1, to obtain a solid catalyst of Comparative Production Example 7.

[0166] Comparative Production Example 8 A solid catalyst of Comparative Production Example 8 was obtained by performing the zeolite treatment step and the calcination step in the same manner as in Comparative Production Example 1, except that in Comparative Production Example 7, 0.61 g (by mass) (7.20 mmol) of sodium nitrate was added to pure water to completely dissolve it, thereby preparing a 0.14 mol / L aqueous sodium nitrate solution, and instead 0.40 g (by mass) (10.00 mmol) of sodium hydroxide (NaOH, manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.) was added to pure water to completely dissolve it, thereby preparing a 0.20 mol / L aqueous sodium hydroxide solution.

[0167] <Measurement of Acid Amount of Solid Catalyst (Zeolite)> The acid amounts of the MFI zeolite (zeolite a) of Reference Production Example 1, the FAU zeolite (zeolite b), and the MFI zeolite (zeolite c) (hereinafter, these may be collectively referred to as "raw material zeolites") used as raw materials in the production of the solid catalysts of Production Examples 1 to 3 and Comparative Production Examples 1 to 4 and 6 to 8 were analyzed by ammonia temperature-programmed desorption (TPD) under the following measurement conditions. [Acid amount measurement conditions] Apparatus: BEL-CAT-BASIC (manufactured by Microtrac-Bell Corporation) Detector: quadrupole mass spectrometer BEL-Mass (manufactured by Microtrac-Bell Corporation) Species to be measured: NH ３ (m / z = 16) Pretreatment conditions: Pretreatment was performed in the order of steps 1 to 9 shown in Table 2 below under the conditions shown in Table 1 below. Temperature increase conditions: The temperature was increased from 100°C to 600°C at a rate of 10°C / min, and held at 600°C for 30 minutes. The He gas flow rate during the temperature increase was 30 mL / min.

[0168]

[0169] The acid amount of the MFI zeolite (zeolite a) was 0.037 mmol / g, the acid amount of the FAU zeolite (zeolite b) was 1.0 mmol / g, and the acid amount of the MFI zeolite (zeolite c) was 0.86 mmol / g.

[0170] [Evaluation of Zeolite Properties] The crystal system, BET specific surface area, molar ratio [SiO ２ / Al ２ O ３ The salt concentration in the aqueous solution was analyzed by the following method. The ratio [(valence number × substance amount) of cations in the salt contained in the salt-containing aqueous solution / acid amount of the starting zeolite] of the zeolites obtained in Reference Production Example 1, Production Examples 1 to 3, and Comparative Production Examples 1 to 8 was calculated by the following method. The results are shown in Tables 3-1 and 3-2.

[0171] In addition, in the following Tables 3-1 and 3-2, the cation ion crystal radius of the ions contained in each of the zeolites obtained in Reference Production Example 1, Production Examples 1 to 3, and Comparative Production Examples 1 to 4 and 6 to 8 indicates the value of the crystal radius determined by R. D. Shannon and C. T. Prewitt et al., and the cation element electronegativity indicates the value of Pauling's electronegativity.

[0172] <Analysis of Zeolite Crystal System> The crystal systems of the zeolites obtained in Reference Production Example 1, Production Examples 1 to 3, and Comparative Production Examples 1 to 8 were analyzed by X-ray diffraction (XRD) under the following measurement conditions. [X-ray diffraction measurement conditions] ・ Apparatus: X'Pert Pro MPD (manufactured by Pnalytical) ・ X-ray source: CuKα radiation ・ Incident X-ray side filter: 10 mm brass mask ・ Detector side filter: Ni filter ・ Incident side slit: Sollerslit 0.04 rad ASS 1 / 8° ・ Detector side slit: ASS 5.0 mm Sollerslit 0.04 rad ・ Detector: PIXel1D ・ Measurement method: Reflection method ・ Operation range (measurement range): 2θ = 5° to 120° ・ Step width: 0.006565° ・ Counting time: 78.795 sec / step

[0173] <Measurement of BET specific surface area of ​​zeolite> The BET specific surface area of ​​each of the zeolites obtained in Reference Production Example 1, Production Examples 1 to 3, and Comparative Production Examples 1 to 8 was measured in accordance with ISO 9277:2010 "Determination of the specific surface area of ​​powders (solids) by gas adsorption."

[0174] Specifically, the specific surface area was determined by measurement in accordance with ISO 9277:2010 using a specific surface area measuring device (BELSORP (registered trademark) MAX II, manufactured by Microtrac-Bell Corporation) at liquid nitrogen temperature using nitrogen molecules as a probe, and analysis by the BET method.

[0175] <Mole ratio of solid catalyst (zeolite) [SiO ２ / Al ２ O ３Each solid catalyst obtained in Reference Production Example 1, Production Examples 1 to 3, and Comparative Production Examples 1 to 8 was precisely weighed, and the catalyst was dissolved in nitric acid (EL nitric acid 1.38 for electronics industry, manufactured by Kanto Chemical Co., Ltd., purity 60.0% to 61.0%) and hydrofluoric acid (ultra-high purity reagent Ultrapur ＴＭ The measurement sample was completely dissolved in an aqueous solution containing SiO 2 -100 (purity 46.0% to 51.0%) and adjusted to a constant volume. The Si and Al contents of this measurement sample were measured using an ICP emission spectrometer (PlasmaQuant PQ 9000, manufactured by Analytik Jena AG). The molar ratio [SiO 2 ] was calculated from the number of moles of Si and Al based on the following formula: ２ / Al ２ O ３ The molar ratio [SiO ２ / Al ２ O ３ ] = 2 × (number of moles of Si) / (number of moles of Al)

[0176] <Measurement of Salt Concentration in Aqueous Solution> The salt concentration in each aqueous solution used in the treatment step of Production Examples 1 to 3 and Comparative Production Examples 1 to 4 and 6 to 8 was determined by molar calculation, assuming that there was no change in the liquid volume due to mixing.

[0177] <Calculation of the ratio [(valence × substance amount) of cation in salt contained in salt-containing aqueous solution / acid amount of starting zeolite]> The acid amount of the starting zeolite used in the production of the solid catalysts of Production Examples 1 to 3 and Comparative Production Examples 1 to 4 and 6 to 8 corresponds to the substance amount at which the starting zeolite can provide a cation. Furthermore, the acid amount of the cation (Rb ) in the various salts (rubidium nitrate, sodium nitrate, potassium nitrate, cesium nitrate, strontium nitrate, or sodium hydroxide) contained in the rubidium nitrate aqueous solutions prepared in Production Examples 1 to 3 and Comparative Production Example 6, the sodium nitrate aqueous solutions prepared in Comparative Production Examples 1 and 7, the potassium nitrate aqueous solution prepared in Comparative Production Example 2, the cesium nitrate aqueous solution prepared in Comparative Production Example 3, the strontium nitrate aqueous solution prepared in Comparative Production Example 4, and the sodium hydroxide aqueous solution prepared in Comparative Production Example 8 (hereinafter, these may be collectively referred to as "salt-containing aqueous solutions") is calculated. ＋ , Na ＋ , K. ＋ , Cs＋ , or Sr ２＋ The product of the valence of the cation in the salt contained in the salt-containing aqueous solution and the amount of substance of the cation in the salt contained in the salt-containing aqueous solution was calculated. Next, the ratio of (valence × amount of substance) of the cation in the salt contained in the salt-containing aqueous solution to the amount of acid of the raw zeolite [(valence × amount of substance) of the cation in the salt contained in the salt-containing aqueous solution / amount of acid of the raw zeolite] was calculated. The results are shown in Tables 3-1 and 3-2 below.

[0178]

[0179]

[0180] (Example 1) The solid catalyst obtained in Production Example 1 (hereinafter referred to as "Rb ＋ In the presence of substituted MFI-type zeolite, the decomposition of mixed plastics was carried out by the following method.

[0181] A mixture of 0.3 g of polyethylene (Sigma-Aldrich, number average molecular weight 1,700, weight average molecular weight 4,000), 0.3 g of polypropylene (Sigma-Aldrich, number average molecular weight 5,000, weight average molecular weight 12,000), 0.3 g of polystyrene (Sigma-Aldrich, weight average molecular weight 35,000), and 0.2 g of the solid catalyst of Production Example 1 was placed in a quartz inner cylinder. The inner cylinder was placed in a high-temperature, high-pressure reaction vessel (Model 4790, made of SUS-316, capacity 100 mL, manufactured by Parr) together with nitrogen gas at atmospheric pressure and sealed, and then heated to an internal temperature of 450°C and maintained for 8 hours. After cooling, the gaseous product was recovered, and 10 mL of tetrahydrofuran (THF) (manufactured by Kanto Chemical Co., Inc., high-performance liquid chromatography reagent, stabilizer-free) was added to the residue and mixed well at room temperature. The solid content was filtered off and washed twice with a small amount of THF. In this way, a product soluble in THF (THF-soluble product) was extracted into a THF solution consisting of the combined filtrate and washings.

[0182] (Example 2) In Example 1, the solid catalyst of Production Example 1 was replaced with the solid catalyst of Production Example 2 (hereinafter referred to as "Na ＋ The gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that the zeolite used in Example 1 was changed to a substituted MFI-type zeolite (sometimes referred to as "substituted MFI-type zeolite").

[0183] Example 3 In Example 1, the solid catalyst of Production Example 1 was replaced with the solid catalyst of Production Example 3 (hereinafter, "Na ＋ The gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that the zeolite used in Example 1 was changed to a substituted MFI-type zeolite (sometimes referred to as "substituted MFI-type zeolite").

[0184] Comparative Example 1 In Example 1, the solid catalyst of Production Example 1 was replaced with the solid catalyst of Comparative Production Example 1 (hereinafter, "Na ＋ The gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that the zeolite used in Example 1 was changed to a substituted MFI-type zeolite (sometimes referred to as "substituted MFI-type zeolite").

[0185] Comparative Example 2 In Example 1, the solid catalyst of Production Example 1 was replaced with the solid catalyst of Comparative Production Example 2 (hereinafter referred to as "K ＋ The gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that the solid catalyst was changed to a substituted MFI-type zeolite (sometimes referred to as "substituted MFI-type zeolite").

[0186] Comparative Example 3 In Example 1, the solid catalyst of Production Example 1 was replaced with the solid catalyst of Comparative Production Example 3 (hereinafter, "Cs ＋ The gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that the zeolite used in Example 1 was changed to a substituted MFI-type zeolite (sometimes referred to as "substituted MFI-type zeolite").

[0187] Comparative Example 4 In Example 1, the solid catalyst of Production Example 1 was replaced with the solid catalyst of Comparative Production Example 4 (hereinafter, "Sr ２＋ The gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that the zeolite used in Example 1 was changed to a substituted MFI-type zeolite (sometimes referred to as "substituted MFI-type zeolite").

[0188] Comparative Example 5 The gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that the solid catalyst in Production Example 1 was changed to the solid catalyst (TS-1) in Comparative Production Example 5.

[0189] (Comparative Example 6) In Example 1, the gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that the solid catalyst of Production Example 1 was changed to the solid catalyst of Reference Production Example 1 (hereinafter, sometimes referred to as "unsubstituted MFI zeolite"). (Comparative Example 7) In Example 1, the solid catalyst of Production Example 1 was changed to the solid catalyst of Comparative Production Example 6 (hereinafter, sometimes referred to as "Rb ＋ The gaseous products and the THF-soluble products were extracted in the same manner as in Example 1, except that the zeolite used in Example 1 was changed to a substituted FAU-type zeolite (sometimes referred to as "substituted FAU-type zeolite").

[0190] [Evaluation of Plastic Degradability] 38 mg of cyclopentane (manufactured by Tokyo Chemical Industry Co., Ltd., reagent, purity: 98.0% or higher) was added as an internal standard to each of the gaseous products recovered in Examples 1 to 3 and Comparative Examples 1 to 7 to prepare analytical samples. In addition, 0.12 g of t-butylbenzene (manufactured by Tokyo Chemical Industry Co., Ltd., reagent, purity: 98.0% or higher) was added as an internal standard to each of the THF-soluble products recovered in Example 1 and Comparative Examples 1 to 7 to prepare analytical samples.

[0191] These analytical samples were analyzed using a gas chromatograph (GC) equipped with a flame ionization detector under the following analytical conditions, and each component was quantified from the ratio of the peak area of ​​each component to that of the internal standard. The results are shown in Tables 4-1 and 4-2 below.

[0192] <<GC analysis conditions for gas products>> Apparatus: Nexis GC-2030 (Shimadzu Corporation) Column: Rt-Alumina BOND (diameter: 0.32 mm, length: 30 m, Restek) Carrier gas type: Ar Carrier gas flow rate: 360 mL / min Injection temperature: 200°C Sample injection amount: 1 mL Split ratio: 1 / 200 Column temperature: The temperature rise program was set in the following order: 120°C (9 minutes) → temperature rise (10°C / min) → 200°C (30 minutes) Detector: Flame ionization detector (FID) Detector temperature: 200°C

[0193] <<GC analysis conditions for THF soluble products>> Apparatus: Nexis GC-2030 (Shimadzu Corporation) Column: DB-1 (diameter: 0.25 mm, length: 30 m, Agilent Technology) Carrier gas type: He Carrier gas flow rate: 97 mL / min Injection temperature: 350°C Sample injection amount: 1 μL Split ratio: 1 / 50 Column temperature: The temperature rise program was set in the following order: 35°C (10 min) → temperature rise (5°C / min) → 350°C (10 min) Detector: Flame ionization detector (FID) Detector temperature: 350°C

[0194] In Tables 4-1 and 4-2 below, "olefins having 4 carbon atoms" refers to 1-butene, cis-2-butene, trans-2-butene, and 2-methylpropene. "olefins having 5 carbon atoms" refers to 1-pentene, cis-2-pentene, trans-2-pentene, 2-methyl-1-butene, and 2-methyl-2-butene. "Useful aromatics" refers to benzene, toluene, ethylbenzene, three positional isomers of xylene (p-xylene, m-xylene, and o-xylene), styrene, and cumene. "lower olefins" refers to olefins having 2 to 5 carbon atoms. "useful components" refers to lower olefins and useful aromatics. Furthermore, "O / P ratio" refers to the ratio of "total yield (%) of olefin products having 2 to 5 carbon atoms / total yield (%) of paraffin products having 2 to 5 carbon atoms."

[0195]

[0196]

[0197] From the results of Tables 1, 4-1, and 4-2, among the cations predicted with good results by the prediction model, Rb ＋ The MFI-type zeolite containing β-methyl-2-pyrrolidone (β-methyl-2-pyrrolidone) produced the best yield of useful components and O / P ratio. The yield of useful components and O / P ratio exceeded the results predicted by the prediction model.

[0198] (Test Example 2: Molar ratio of solid catalyst [SiO ２ / Al ２ O３ In Comparative Example 1, the solid catalyst (Na ＋ The solid catalyst of Comparative Production Example 7 (hereinafter referred to as "Na ＋ The gaseous product and the THF-soluble product were extracted in the same manner as in Comparative Example 1, except that the zeolite used was changed to a substituted MFI-type zeolite (sometimes referred to as "substituted MFI-type zeolite").

[0199] The amounts of each component in the resulting gaseous products and THF-soluble products were determined from the ratio of the peak area of ​​each component to that of the internal standard in the same manner as in the evaluation of plastic degradability in Example 1 and Comparative Examples 1 to 7. The results compared with Comparative Example 1 are shown in Table 5 below.

[0200]

[0201] (Test Example 3: Effect of nitrate aqueous solution in treatment process) In Comparative Example 1, the solid catalyst (Na ＋ The solid catalyst of Comparative Production Example 8 (hereinafter referred to as "Na ＋ The gaseous product and the THF-soluble product were extracted in the same manner as in Comparative Example 1, except that the zeolite used was changed to a substituted MFI-type zeolite (sometimes referred to as "substituted MFI-type zeolite").

[0202] The amounts of each component in the resulting gaseous products and THF-soluble products were determined from the ratio of the peak area of ​​each component to that of the internal standard in the same manner as in the evaluation of plastic degradability in Example 1 and Comparative Examples 1 to 7. The results compared with Comparative Example 1 are shown in Table 6 below.

[0203]

[0204] Comparative Example 8 The gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that the solid catalyst in Production Example 1 was changed to the solid catalyst (zeolite a) in Reference Production Example 1.

[0205] Example 4 The gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that 0.2 g of the solid catalyst of Production Example 1 was added to 0.3 g of polyethylene, 0.3 g of polypropylene, and 0.3 g of polystyrene in Example 1, but 0.135 g of the solid catalyst of Production Example 1 was added to 0.3 g of polyethylene, 3 g of polypropylene, and 0.3 g of polystyrene.

[0206] Example 5 The gaseous product and the THF-soluble product were extracted in the same manner as in Example 1, except that 0.2 g of the solid catalyst of Production Example 1 was added to 0.3 g of polyethylene, 0.3 g of polypropylene, and 0.3 g of polystyrene in Example 1, but 0.225 g of the solid catalyst of Production Example 1 was added to 0.3 g of polyethylene, 3 g of polypropylene, and 0.3 g of polystyrene.

[0207] [Evaluation of Plastic Degradability] Analytical samples of the gaseous products and THF-soluble products recovered in Comparative Example 8, Example 4, and Example 5 were prepared in the same manner as in the evaluation of plastic degradability in Examples 1 to 3 and Comparative Examples 1 to 7. These samples were analyzed under the above-mentioned analytical conditions using a gas chromatograph (GC) equipped with a flame ionization detector, and each component was quantified based on the ratio of the peak area of ​​each component to that of the internal standard. The results are shown in Table 7 below. The results of Example 1 are also shown in Table 7 below.

[0208] In Table 7 below, the "amount added [phr]" of the solid catalyst indicates the mass parts of the solid catalyst added when the total mass (0.9 g) of polyethylene, polypropylene, and polystyrene is taken as 100 mass parts.

[0209]

[0210] As described above, the present disclosure has been described based on specific embodiments, manufacturing examples, and examples. However, these embodiments, manufacturing examples, and examples are presented merely as examples, and the present disclosure is not limited to the above embodiments, manufacturing examples, and examples. The above embodiments can be implemented in various other forms, and various combinations, omissions, substitutions, additions, modifications, etc. can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as set forth in the claims.

[0211] This international application claims priority based on Japanese Patent Application No. 2023-131007, filed on August 10, 2023, the entire contents of which are incorporated herein by reference.

[0212] REFERENCE SIGNS LIST 1 Information processing system 10 Design support device 11 Learning device 12 User terminal 28 Parameter generation unit 30 Prediction unit 32 Candidate output unit 52 Learning dataset acquisition unit 54 Learning unit

Claims

1. A method for producing an olefin-containing composition comprising decomposing a plastic in the presence of a zeolite to produce an olefin having 2 to 5 carbon atoms, the zeolite being selected from the group consisting of Rb ＋ 1. A method for producing an olefin-containing composition, comprising the step of:

2. The method for producing an olefin-containing composition according to claim 1, wherein the plastic is a polyolefin.

3. The method for producing an olefin-containing composition according to claim 1, wherein the plastic contains at least one selected from the group consisting of polyethylene, polypropylene, and polystyrene.

4. A method for producing an olefin-containing composition according to claim 1 or 2, wherein the temperature at which the plastic is decomposed is 300°C or higher and 1,100°C or lower.

5. The Rb ＋ The Al content of MFI-type zeolite ２ O ３ SiO ２ Molar ratio [SiO ２ / Al ２ O ３ 3. The method for producing an olefin-containing composition according to claim 1 or claim 2, wherein the value of n is 10 or more and 10,000 or less.

6. The Rb ＋ The BET specific surface area of ​​the MFI type zeolite containing ２ / g or more 1,000m ２ The method for producing an olefin-containing composition according to claim 1 or claim 2, wherein the olefin-containing composition has a molecular weight of 1 / g or less.

7. A mixing step of mixing MFI type zeolite with a liquid containing a rubidium compound to obtain a mixed liquid, and calcining the mixed liquid in air to obtain the Rb ＋ The method for producing an olefin-containing composition according to claim 1, further comprising a calcination step to obtain an MFI-type zeolite containing 8. In the mixing step, the mass of the MFI zeolite is x (g), and the Al content of the MFI zeolite is ２ O ３ SiO ２ Molar ratio [SiO ２ / Al ２ O ３ 8. The method for producing an olefin-containing composition according to claim 7, wherein 1≦yz / x≦10,000 is satisfied, where y is the molar ratio of the rubidium compound and z (mmol) is the number of moles of the rubidium compound.

9. The MFI type zeolite is H ＋ The method for producing an olefin-containing composition according to claim 7, wherein the zeolite is an MFI type zeolite containing:

10. A catalyst for use in the production of an olefin-containing composition containing an olefin having 2 to 5 carbon atoms, comprising Rb ＋ A catalyst for producing an olefin-containing composition, comprising an MFI type zeolite containing

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