Method for producing chemical product and apparatus for producing chemical product

Abstract

A method for producing a chemical product according to the present disclosure includes pyrolyzing a plastic-containing raw material in a steam atmosphere.

Description

Chemical manufacturing method and chemical manufacturing apparatus

[0001] This disclosure relates to a method for producing chemicals and an apparatus for producing chemicals.

[0002] One method of recycling waste plastics is chemical recycling, which involves breaking down waste plastics, converting them into monomers and gases, or using them as reducing agents for blast furnaces or raw materials for coke ovens.

[0003] For example, Patent Document 1 discloses a waste plastic treatment method in which waste plastics are vaporized by thermal decomposition, the resulting thermal decomposition gas is brought into contact with a gallium-containing silicate catalyst, and catalytic reaction products are recovered. In this method, a fixed-bed treatment apparatus filled with a gallium-containing silicate catalyst may be used. Specifically, it is disclosed that granular gallium silicate is filled as a fixed bed, molten polyethylene is continuously supplied alone, and thermal decomposition and vaporization are carried out at a temperature of 425 to 525°C while simultaneously contacting the gallium silicate to obtain benzene, toluene, and xylene.

[0004] Furthermore, Patent Document 2 discloses a method for producing olefins, which includes the steps of heating a polyolefin-based plastic to obtain decomposition products, and contacting the obtained decomposition products with an MFI-type zeolite containing 0.10% to 0.30% by mass of sodium atoms to obtain a catalytic decomposition product containing an olefin. Specifically, it is disclosed that an MFI-type zeolite containing sodium atoms is filled into a downstream reaction tube, polyethylene, polypropylene, or a mixture thereof is flowed from an upstream reaction tube to a downstream reaction tube, and thermally decomposed at 525°C while in contact with the MFI-type zeolite containing sodium atoms to obtain an olefin having 2 to 3 carbon atoms.

[0005] Furthermore, a fluidized bed reactor is generally used in continuous reactors that use aromatic plastics such as polystyrene, chlorine-containing plastics such as polyvinyl chloride, and mixed plastics containing polyolefins as raw materials to obtain basic chemicals in a single stage without going through intermediate products such as pyrolysis oils. For example, Patent Document 3 discloses a method for producing olefins and aromatic compounds from the raw materials by introducing hydrocarbon feedstock such as plastics and a catalyst composition into a fluidized bed reactor.

[0006] On the other hand, in the thermal decomposition of waste plastics, it is known that the surfaces of the reactor, the filler in the fixed-bed reaction section, and the fluidizing agent in the fluidized-bed reaction section become carbonized (sometimes referred to as "coking" in this disclosure), and the efficiency of product production decreases over time.

[0007] Japanese Patent Publication No. 2001-316517, International Publication No. 2021 / 166854, Japanese Patent Publication No. 2016-513147

[0008] The present disclosure aims to provide a method for producing chemicals that can suppress coking and efficiently obtain at least one chemical selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons in high yield.

[0009] The means for solving the above problems are as follows: <1> A method for producing a chemical product, characterized in that it includes thermal decomposition of a raw material containing plastic under a water vapor atmosphere. <2> The method for producing a chemical product according to <1>, wherein the water vapor concentration in the water vapor atmosphere is 10% by volume or more during the thermal decomposition. <3> The method for producing a chemical product according to <1> or <2>, wherein the thermal decomposition is carried out under a mixed gas atmosphere of water vapor and an inert gas other than water vapor. <4> The method for producing a chemical product according to any one of <1> to <3>, wherein the thermal decomposition is carried out in a fixed-bed reaction section having a filler layer filled with filler. <5> The method for producing a chemical product according to any one of <1> to <3>, wherein the thermal decomposition is carried out in a reaction section containing a fluidizing agent, and includes supplying at least water vapor from one end of the reaction section containing the fluidizing agent to cause the fluidizing agent to flow. <6> A method for producing a chemical product according to any one of <1> to <5> above, wherein the heating temperature for the thermal decomposition is 600°C or higher and 1,200°C or lower. <7> A method for producing a chemical product according to any one of <1> to <6> above, wherein the raw material containing the plastic contains waste plastic. <8> A method for producing a chemical product according to any one of <1> to <7> above, wherein the raw material containing the plastic contains 50% by mass or more of polyolefin. <9> A method for producing a chemical product according to any one of <1> to <8> above, wherein the chemical product contains at least one chemical product selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons. <10> A chemical product production apparatus comprising: a reaction section; a raw material supply section connected to the reaction section for supplying raw materials containing plastic into the reaction section; a steam supply section connected to the reaction section for supplying steam into the reaction section; and a heating section for heating the reaction section. <11> The chemical manufacturing apparatus according to <10>, further comprising an inert gas supply unit connected to the reaction unit and supplying an inert gas other than water vapor to the reaction unit.<12> The chemical manufacturing apparatus according to <10> or <11>, wherein the reaction section is a fixed-bed reaction section having a filler layer filled with filler. <13> The chemical manufacturing apparatus according to <10>, wherein the reaction section contains a fluid material inside, and the steam supply section is connected to one end of the reaction section and is arranged to supply the steam to the fluid material from a direction opposite to the direction of gravity.

[0010] According to embodiments of this disclosure, it is possible to provide a method for producing chemicals that can suppress coking and efficiently obtain at least one chemical selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons in high yield.

[0011] Figure 1 is a diagram showing an example of a flowchart of the method for manufacturing a chemical product according to the present disclosure. Figure 2 is a diagram showing another example of a flowchart of the method for manufacturing a chemical product according to the present disclosure. Figure 3 is a schematic cross-sectional view showing an example of a chemical product manufacturing apparatus according to the first embodiment of the present disclosure. Figure 4A is a schematic diagram showing an example of a cross-section parallel to the filler deposition direction in the filler layer of the reaction section. Figure 4B is a schematic diagram of the line IVB-IVB in Figure 4A. Figure 5 is a schematic cross-sectional view showing an example of a chemical product manufacturing apparatus according to the second embodiment of the present disclosure.

[0012] The methods disclosed in Patent Documents 1 to 3 only disclose methods for the thermal decomposition of polyolefins alone, and do not disclose methods for efficiently thermally decomposing mixed plastics or waste plastics containing aromatic plastics, chlorine-containing plastics, polyolefins, etc., and producing useful components in high yield.

[0013] Different types of plastics exhibit characteristic thermal decomposition patterns. Therefore, waste plastics and mixed plastics containing various components are difficult to decompose under consistent conditions.

[0014] Furthermore, aromatic and chlorine-containing plastics typically have lower decomposition temperatures compared to polyolefins. Therefore, when these are mixed into a plastic, heating at the decomposition temperature of polyolefins causes the aromatic and chlorine-containing plastics to carbonize (coke). As a result, useful components cannot be obtained from the aromatic and chlorine-containing plastics, leading to a decrease in the yield of useful components. Moreover, when using a fixed-bed reactor, there is a risk that the flow paths for raw materials and decomposition products may become blocked by coking. In addition, when using a fluidized-bed reactor, there is a risk that the fluidizing agent may become difficult to flow due to coking.

[0015] In response to this, the inventors conducted diligent research and found that by thermally decomposing raw materials containing plastics under a steam atmosphere, coking can be suppressed, and at least one chemical selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons can be obtained efficiently and in high yield. Furthermore, by suppressing coking, it is expected that the lifespan of the chemical manufacturing equipment can be extended.

[0016] Embodiments of this disclosure will be described below with reference to the drawings. However, the embodiments of this disclosure are not limited to the following description, but are illustrative examples of chemical manufacturing methods and chemical manufacturing apparatus for embodying the technical concept of the present invention, and can be modified as appropriate without departing from the gist of this disclosure. Furthermore, in this disclosure, the "~" indicating a numerical range means that the numerical values ​​before and after it are included as the lower and upper limits, respectively, unless otherwise specified.

[0017] In the following explanation, terms indicating specific directions or positions (e.g., "up," "down," and other terms including these) will be used as needed. However, the use of these terms is solely to facilitate understanding of the invention by referring to the drawings, and the technical scope of the invention is not excessively limited by the meaning of these terms. For example, if "top surface" is mentioned, the invention must not always be used in a way that it faces upwards. Also, parts with the same reference numerals appearing in multiple drawings indicate the same or equivalent parts or components.

[0018] Furthermore, in this disclosure, the term "polygon" refers to polygons such as triangles and quadrilaterals, including shapes where the corners of the polygon have been rounded, chamfered, or otherwise modified. Similarly, shapes where modifications have been made not only to the corners (ends of the sides) but also to the middle parts of the sides will also be referred to as polygons. In other words, shapes that retain the shape of a polygon but have been partially modified are included in the interpretation of "polygon" as described in this disclosure.

[0019] Furthermore, the same applies not only to polygons, but also to words describing specific shapes such as trapezoids, circles, and concave shapes. The same also applies when dealing with each side that forms such a shape. In other words, even if a side has been processed at a corner or in the middle, the interpretation of "side" includes the processed part. When distinguishing a "polygon" or "side" without partial processing from a processed shape, the term "strictly" should be added, for example, "strictly quadrilateral."

[0020] Furthermore, unless otherwise specified, the sizes, materials, shapes, and relative arrangements of the components described below are intended to be illustrative examples of the embodiments of this disclosure, and are not intended to limit the scope to those embodiments. Also, the content described in one embodiment may be applicable to other embodiments and modifications. Additionally, the sizes and positional relationships of the members shown in the drawings may be exaggerated for clarity. Moreover, to avoid overly complex drawings, schematic diagrams may be used with some elements omitted, or end views showing only the cross-section may be used as cross-sectional views.

[0021] (Method for producing chemicals) The method for producing chemicals according to this disclosure includes thermal decomposition of raw materials, including plastics, under a water vapor atmosphere. The method for producing chemicals according to this disclosure may further include other treatments as necessary.

[0022] Figure 1 is a diagram showing an example of a flowchart for the method of producing the chemical product of this disclosure.

[0023] <<Chemicals>> The chemicals produced by the chemical manufacturing method of this disclosure are not particularly limited as long as they are chemicals obtained by decomposing raw materials including plastics, and can be appropriately selected depending on the purpose, but it is preferable that the chemicals include at least one selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons.

[0024] In addition, the chemicals produced by the chemical manufacturing method of this disclosure may include by-products in addition to the chemical containing at least one selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons. In such cases, the chemicals in this disclosure shall include both the chemical containing at least one selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons and the by-products.

[0025] In this disclosure, "useful component" means at least one chemical selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons.

[0026] In this disclosure, “minor component” means a component other than at least one chemical selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons, contained in a chemical product.

[0027] -Olefins having 2 to 5 carbon atoms- In the method for producing chemicals according to the present disclosure, olefins having 2 to 5 carbon atoms may be referred to as "lower olefins". The olefin having 2 to 5 carbon atoms is preferably at least one selected from the group consisting of alkenes having 2 to 5 carbon atoms and dienes having 2 to 5 carbon atoms, and alkenes having 2 to 5 carbon atoms are more preferred.

[0028] An example of an olefin with two carbon atoms is ethylene.

[0029] An example of an olefin with three carbon atoms is propylene.

[0030] Examples of olefins with four carbon atoms include trans-2-butene, 1-butene, isobutene, cis-2-butene, and butadiene.

[0031] As the olefin having 5 carbon atoms, for example, trans-2-pentene, 2-methyl-2-butene, 1-pentene, 2-methyl-1-butene, cis-2-pentene, isoprene, cyclopentadiene and the like can be mentioned.

[0032] The total yield (mass%) of olefins having 2 to 5 carbon atoms is not particularly limited and can be appropriately selected according to the purpose. However, it is preferably 42 mass% or more, more preferably 43 mass% or more, and still more preferably 45 mass% or more based on the total mass of the raw material containing plastic. The total yield (mass%) of olefins having 2 to 5 carbon atoms based on the total mass of the raw material containing plastic is preferably as high as possible, and the upper limit value is not particularly limited. For example, it may be 90 mass% or less or 80 mass% or less. The lower limit value and the upper limit value of the total yield (mass%) of olefins having 2 to 5 carbon atoms based on the total mass of the raw material containing plastic can be appropriately combined. For example, 42 mass% or more and 90 mass% or less, 43 mass% or more and 90 mass% or less, 45 mass% or more and 90 mass% or less, 42 mass% or more and 90 mass% or less, 43 mass% or more and 80 mass% or less, 45 mass% or more and 80 mass% or less, etc. can be mentioned.

[0033] In the present disclosure, the yield of each component or the total yield of each component based on the total mass of the raw material containing plastic is expressed in "mass%".

[0034] Olefins having 2 to 5 carbon atoms can be used as basic chemicals suitable for chemical recycling and can be a raw material for polyolefins. Polyolefins can be suitably used in various fields such as plastic bags, wrap films, straws, medical devices, home appliance housings, erasers, hoses, tires, tubes, CD cases, food trays, food containers, plastic bottles, fibers and the like.

[0035] - Aromatic hydrocarbons - The aromatic hydrocarbons are not particularly limited, but benzene, toluene, ethylbenzene, three positional isomers of xylene (p-xylene, m-xylene, and o-xylene), styrene and the like are preferable.

[0036] In this disclosure, benzene, toluene, ethylbenzene, and the three positional isomers of xylene (p-xylene, m-xylene, and o-xylene), as well as styrene, may be referred to as "useful aromatic hydrocarbons."

[0037] There are no particular restrictions on the total yield (mass%) of useful aromatic hydrocarbons, and it can be appropriately selected depending on the purpose. However, it is preferably 10% by mass or more, more preferably 12% by mass or more, and even more preferably 13% by mass or more, relative to the total mass of the raw materials including plastic. A higher total yield (mass%) of useful aromatic hydrocarbons relative to the total mass of the raw materials including plastic is preferable, and there are no particular restrictions on its upper limit. For example, it may be 50% by mass or less, or 30% by mass or less. The lower and upper limits of the total yield (mass%) of useful aromatic hydrocarbons relative to the total mass of the raw materials including plastic can be appropriately combined. For example, 10% by mass or more and 50% by mass or less, 12% by mass or more and 50% by mass or less, 13% by mass or more and 50% by mass or less, 10% by mass or more and 30% by mass or less, 12% by mass or more and 30% by mass or less, 13% by mass or more and 30% by mass or less, etc.

[0038] -By-products- Chemicals obtained by the chemical manufacturing methods of this disclosure may contain by-products. Examples of by-products include paraffin, carbon, and hydrogen gas. Carbon as a by-product refers to a composition consisting only of carbon atoms, and examples include soot, graphite, and diamond.

[0039] In this disclosure, "paraffin" refers to an aliphatic saturated hydrocarbon having 2 to 5 carbon atoms, preferably a chain-like aliphatic saturated hydrocarbon having 2 to 5 carbon atoms.

[0040] Specific examples of paraffins include ethane, propane, iso-butane, n-butane, isopentane, and n-pentane.

[0041] There are no particular restrictions on the total yield (mass%) of paraffins having 1 to 5 carbon atoms, but it is preferably 35% by mass or less, more preferably 30% by mass or less, even more preferably 10% by mass or less, and particularly preferably 5% by mass or less, relative to the total mass of the raw materials including plastic. The lower limit of the total yield (mass%) of paraffins having 1 to 5 carbon atoms is preferable as it is lower, for example, 0.1% by mass or more relative to the total mass of the raw materials including plastic.

[0042] The yield of useful components and by-products contained in the chemical can be determined by analyzing the gaseous and liquid chemical products obtained by the chemical manufacturing method of this disclosure using gas chromatography (GC) equipped with a flame ionization detector.

[0043] When analyzing gaseous chemical products, the analysis can be performed using gas chromatography (GC) equipped with a flame ionization detector under the analytical conditions described in the examples. Each component can then be quantified using the internal standard method, based on the ratio of the peak area of ​​each component to that of the internal standard. The internal standard is not particularly limited as long as it is stable under the analytical conditions and easily separated from the analyte; for example, cyclopentane can be used.

[0044] Furthermore, when analyzing liquid substances as chemicals, the analysis can be performed using gas chromatography (GC) equipped with a flame ionization detector under the analytical conditions described in the examples, and each component can be quantified using the internal standard method based on the ratio of the peak area of ​​each component to that of the internal standard. The internal standard is not particularly limited as long as it is stable under the analytical conditions and easily separated from the analyte; for example, cyclopentane can be used.

[0045] Furthermore, the amount of coking, a by-product contained in the chemical, can be calculated by removing the filler layer from the reaction chamber, or the filler constituting the filler layer, from the reaction chamber and burning it in air, and then measuring the weight change before and after air calcination. Specifically, the calcination weight loss rate (mass%) described in the examples can be evaluated as the amount of coking.

[0046] <Thermal Decomposition S1> In thermal decomposition S1, the raw materials containing plastic are thermally decomposed in a water vapor atmosphere.

[0047] In the thermal decomposition process S1, there are no particular restrictions on the water vapor concentration in the water vapor atmosphere, and it can be appropriately selected according to the purpose, but it is preferably 10% by volume or more, more preferably 25% by volume or more, and even more preferably 35% by volume or more. 50% by volume or more is particularly preferred. When the water vapor concentration in the water vapor atmosphere is 10% by volume or more, coking can be suppressed and the yield of useful components can be improved. Furthermore, in the thermal decomposition process S1, there are no particular restrictions on the upper limit of the water vapor concentration in the water vapor atmosphere, but it is preferable that the partial pressure of water vapor in the water vapor flow section 4e, reaction section 1, and outlet section 8a does not exceed the saturated vapor pressure so that the water vapor does not partially liquefy and obstruct the flow of inert gases other than water vapor or chemicals R.

[0048] In the thermal decomposition process S1, there are no particular restrictions on the heating temperature for heating the raw material containing plastic, and it can be appropriately selected according to the purpose, but 600°C or higher is preferred, 700°C or higher is more preferred, 750°C or higher is even more preferred, and 800°C or higher is particularly preferred. When the heating temperature for heating the raw material containing plastic is 600°C or higher, coking can be suppressed and the yield of useful components can be improved. Furthermore, there are no particular restrictions on the upper limit of the heating temperature for heating the raw material containing plastic, but 1,200°C or lower is preferred, 1,000°C or lower is more preferred, and 980°C or lower is even more preferred. When the heating temperature for heating the raw material containing plastic is 1,200°C or lower, coking can be suppressed and the yield of useful components can be improved.

[0049] The upper and lower limits of the heating temperature for heating the raw materials containing plastic can be combined as appropriate, but 600°C to 1,200°C is preferred, 700°C to 1,200°C is more preferred, 750°C to 1,000°C is even more preferred, and 800°C to 980°C is even more preferred.

[0050] The thermal decomposition S1 is preferably carried out in the reaction section. There are no particular restrictions on the method of heating the reaction section, and it can be appropriately selected according to the purpose. It may be an external heating method in which the reaction section is heated by heat transfer from the outside, or an internal heating method in which the filler or fluid material itself in the reaction section generates heat. Among these, the external heating method is preferred as the method of heating the reaction section.

[0051] The thermal decomposition S1 is carried out while heating the reaction section. However, there are no particular restrictions on the timing of starting the heating in the thermal decomposition S1. The reaction section may be heated in advance before adding the raw material containing plastic to the reaction section, or heating may be started at the same time as adding the raw material containing plastic to the reaction section. However, heating the reaction section in advance is preferable because the raw material containing plastic comes into contact with the reaction section when it has reached the desired temperature, resulting in better thermal decomposition efficiency.

[0052] In the thermal decomposition process S1, there are no particular restrictions on the pressure of the reaction chamber, and it can be appropriately selected depending on the purpose, but from the viewpoint of energy efficiency, 0.09 MPa to 0.95 MPa is preferred.

[0053] The thermal decomposition S1 is carried out in a water vapor atmosphere, but it is even more preferable to carry it out in a mixed gas atmosphere of water vapor and an inert gas other than water vapor.

[0054] There are no particular restrictions on the inert gas other than water vapor, but a gas that is stable in the heating temperature range of S1 during thermal decomposition is preferred. Specific examples of inert gases other than water vapor include nitrogen gas, carbon dioxide, and noble gases. These may be used individually or in combination of two or more. Among these, nitrogen gas is preferred as the inert gas due to its industrial availability and low cost.

[0055] <<Reaction Section>> The reaction section may be a fixed-bed reaction section or a fluidized-bed reaction section.

[0056] - Fixed-bed reaction section - The fixed-bed reaction section has a filler layer filled with filler. The filler is arranged in the internal space of the reaction section. In this disclosure, "fixed bed" means a reaction vessel in which the filler remains fixed even when water vapor and, if necessary, an inert gas other than water vapor are passed through the filler during thermal decomposition S1.

[0057] The fixed-bed reaction section has a certain internal space that can accommodate fillers and ensures a flow path for raw materials, including plastics, and water vapor.

[0058] There are no particular restrictions on the shape, structure, and size of the fixed-bed reaction section, and they can be appropriately selected according to the purpose. However, from the viewpoint of allowing smooth flow of raw materials containing plastics and chemicals, and ensuring sufficient contact time between the raw materials containing plastics and the fillers, it is preferable that the flow direction of the raw materials containing plastics is in the longitudinal direction.

[0059] - Fluidized Bed Reaction Section - The fluidized bed reaction section is a reaction section that contains a fluidizing agent. In the fluidized bed reaction section, the fluidizing agent is made to flow during the thermal decomposition of raw materials, including plastics. The fluidizing agent is placed in the internal space of the reaction section. When thermal decomposition S1 is carried out in the reaction section containing the fluidizing agent, it is preferable to supply at least steam from one end of the reaction section containing the fluidizing agent to make the fluidizing agent flow.

[0060] In this disclosure, "making the fluid material fluid" refers to a reaction vessel in which the fluid material is suspended by passing water vapor, and optionally an inert gas, through it at a sufficient speed, thereby causing the fluid material to behave like a fluid. In such a reaction system, the fluid material may be referred to as "fluidized sand."

[0061] There are no particular restrictions on the shape, structure, and size of the fluidized bed reaction section, and they can be appropriately selected according to the purpose. However, from the viewpoint of allowing smooth flow of raw materials containing plastics and chemicals, and ensuring sufficient contact time between the raw materials containing plastics and the fillers, it is preferable that the flow direction of the raw materials containing plastics is in the longitudinal direction.

[0062] When the reaction section is a fluidized bed reaction section, the method for producing the chemical product of this disclosure preferably includes fluidizing a fluidizing agent. Fluidizing the fluidizing agent can be done by supplying at least steam from one end of the fluidized bed reaction section, and it is preferable that the flow direction of the raw materials, including plastic, is in the longitudinal direction, and that at least steam is supplied from one end in the longitudinal direction, and it is even more preferable that steam, and optionally an inert gas, be supplied to the fluidizing agent from the direction opposite to the direction of gravity in the longitudinal direction of the fluidized bed reaction section.

[0063] The fluidized bed reaction section preferably has a certain internal space that can accommodate the fluidized material and secures a flow path for raw materials including plastics, a flow path for water vapor, and, if necessary, a flow path for inert gas.

[0064] --Filler or Fluidized Material-- The filler forming the filler layer in the fixed-bed reaction section and the fluidized material in the fluidized-bed reaction section can be made from the same materials.

[0065] There are no particular restrictions on the material of the filler or fluid material, and it can be appropriately selected according to the purpose, but it is preferable that it does not react with water vapor, and it is more preferable that it contains as a main component one selected from the group consisting of silicon dioxide, zirconium oxide, yttria-stabilized zirconium oxide, calcia-stabilized zirconium oxide, silicon carbide, silicon nitride, silicon oxide, tantalum oxide, niobium oxide, beryllium oxide, lanthanum oxide, manganese(II) oxide, chromium(III) oxide, gallium oxide, forstenite, and cordierite.

[0066] In this disclosure, the “main component” of the filler or fluid material means the component that accounts for the largest mass percentage of the total mass of the filler or fluid material.

[0067] Furthermore, the filler or fluid material may be coated on its surface with a conductive ceramic such as tungsten oxide, molybdenum(VI) oxide, molybdenum disilicide, lanthanum chromium, triiron tetroxide, copper(I) oxide, tin dioxide, or indium oxide, so as to stabilize in the atmosphere when heating the raw materials including plastic.

[0068] There are no particular restrictions on the film thickness of the filler or fluid coating, and it can be appropriately selected depending on the purpose. However, from the viewpoint of not hindering heat conduction between the filler or fluid, it is preferably 0.001 μm to 5 μm.

[0069] There are no particular limitations on the method for coating the surface of the filler or fluid material. A known method can be appropriately selected depending on the material, shape, structure, and size of the filler or fluid material. For example, a method of coating with a ceramic raw material such as tungsten oxide using a spray coating method, printing method, immersion method, dispenser coating method, etc. A ceramic coating can be formed on the surface of the filler or fluid material coated with the ceramic raw material by firing it using a known method.

[0070] Furthermore, the filler or fluid material may be coated by a dry method such as physical vapor deposition, chemical vapor deposition, or sputtering, or the surface of the filler or fluid material itself may be oxidized to form an oxide film of the aforementioned thickness.

[0071] Furthermore, a catalyst suitable for the purpose of heat treatment may be supported on the surface of the filler or fluid material. There are no particular restrictions on the type of catalyst, and examples include various zeolites and FCC catalysts. The catalyst supported on the surface of the filler or fluid material may be an unused catalyst or a catalyst that has been used in heat treatment one or more times.

[0072] The structure of surface-treated fillers or fluid materials can be confirmed, for example, by observation using a scanning electron microscope (SEM), a transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), or micro-Raman spectroscopy.

[0073] Among these, it is preferable that the filler or fluid material mainly contains silicon dioxide or a surface-treated version thereof. Commercially available products can be used as fillers or fluid materials mainly containing silicon dioxide. Examples include the trade names CARiACT Q-10 (particle size: 1.18 mm to 2.36 mm, manufactured by Fuji Silicia Chemical Co., Ltd.), Ube Silica Sand No. 5 (particle size: 1.7 mm to 0.2 mm, manufactured by Ube Sand Industry Co., Ltd.), and Ube Silica Sand No. 6 (particle size: 0.6 mm to 0.07 mm, manufactured by Ube Sand Industry Co., Ltd.).

[0074] The filler or fluid material may be unused, may be used in heat treatment once or more times, or may be recycled by firing in air after being used in heat treatment once or more times.

[0075] The shape of the filler or fluid particles may be fixed or amorphous.

[0076] There are no particular restrictions on the particle size of the filler or fluid material, and it can be appropriately selected depending on the purpose. Examples include 1.7 mm to 0.2 mm and 0.6 mm to 0.07 mm. These may be used individually or in combination of two or more. Among these, a particle size of 0.6 mm to 0.07 mm is preferred for the filler or fluid material from the viewpoint of the yield of the active ingredient. The particle size of the filler or fluid material is measured by a sieve test (ISO 2591-1:1988).

[0077] There are no particular restrictions on the pore volume of the filler or fluid material, and it can be appropriately selected depending on the purpose, but 0.0001 cm³ is a reasonable value. ３ / g or more 10cm ３ Preferably less than / g, and 0.01 cm ３ / g or more 8cm ３ It is more preferable that the pore volume of the filler or fluid material is 0.0001 cm³ or less. ３ / g or more 8cm ３If it is 1 g or less, it is preferable in that it is easy to maintain a suitable filler layer or a fluid state even during long-term operation using easily available materials. The pore volume of the filler or fluidizing agent is measured in accordance with ISO 15901-2:2006 and analyzed by the BET method.

[0078] The specific surface area of the filler or fluidizing agent is not particularly limited and can be appropriately selected according to the purpose. However, it is 0.1 m ２ / g or more and 3,000 m ２ / g or less, preferably 0.3 m ２ / g or more and 1,000 m ２ / g or less is more preferable. When the specific surface area of the filler or fluidizing agent is 0.1 m ２ / g or more and 1,000 m ２ / g or less, it is preferable in that it is easy to maintain a suitable filler layer or a fluid state even during long-term operation using easily available materials. The specific surface area of the filler or fluidizing agent is measured in accordance with ISO 9277:2010 using a specific surface area measuring device (for example, BELSORP (registered trademark) MAX II, manufactured by MicrotracBEL Corporation) at liquid nitrogen temperature with nitrogen molecules as a probe.

[0079] The filler or fluidizing agent may contain other components other than the main component. The other components in the filler or fluidizing agent are not particularly limited and can be appropriately selected according to the purpose. However, it is preferably a material that is stable in the temperature range of thermal decomposition in S1, is not reduced by by-products such as carbon and hydrogen generated by the thermal decomposition of plastics, and does not react with water vapor.

[0080] The content of the other components in the filler or fluidizing agent is not particularly limited and can be appropriately selected according to the purpose.

[0081] <<Raw Materials Containing Plastics>> There are no particular restrictions on the type of plastic used in raw materials containing plastics; they can be appropriately selected according to the purpose. Examples include mixed plastics containing polyolefins, aromatic plastics, and chlorine-containing plastics. These may be used individually or in combination of two or more types. Furthermore, raw materials containing plastics may also contain other components besides plastics as needed.

[0082] --Mixed Plastics-- There are no particular restrictions on the polyolefins included in the mixed plastics, and they can be appropriately selected depending on the purpose, but it is preferable that they include polyethylene (PE) and polypropylene (PP), which are commonly used in beverage and food containers, packaging materials, molded products, films, etc.

[0083] There are no particular restrictions on the yield of polyolefin in the raw materials containing plastics, and it can be appropriately selected depending on the purpose. However, it is preferably 50% by mass or more, more preferably 50% by mass or more and 90% by mass or less, and even more preferably 60% by mass or more and 85% by mass or less, based on the total mass of the raw materials containing plastics.

[0084] - Aromatic Plastics - Aromatic plastics are plastics that have an aromatic skeleton. There are no particular restrictions on aromatic plastics, and they can be appropriately selected from those commonly used for beverage and food containers, packaging materials, molded products, films, etc., depending on the purpose. Examples include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), acrylonitrile-butadiene-styrene copolymer, polycarbonate (PC), and polystyrene (PS). These may be contained individually or in combination of two or more. Among these, aromatic plastics that contain polyethylene terephthalate (PET) and polystyrene (PS) are preferred.

[0085] -Chlorine-containing plastics- There are no particular restrictions on chlorine-containing plastics, and they can be appropriately selected depending on the purpose. However, it is preferable that they contain at least one selected from the group consisting of polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), and chlorinated polyethylene (CPE), which are commonly used in beverage and food containers, packaging materials, molded products, films, etc.

[0086] There are no particular restrictions on the content of at least one selected from the group consisting of aromatic plastics and chlorine-containing plastics in the plastic, and it can be appropriately selected according to the purpose. However, it is preferably 50% by mass or less, and more preferably 40% by mass or less, relative to the total mass of the raw material containing the plastic. When the yield of at least one selected from the group consisting of aromatic plastics and chlorine-containing plastics in the raw material containing the plastic is 50% by mass or less, useful components can be obtained efficiently with high yield. Furthermore, the lower the content of at least one selected from the group consisting of aromatic plastics and chlorine-containing plastics, the better. The lower limit may be, for example, 0.1% by mass or more, 0.5% by mass or more, 5% by mass or more, or 10% by mass or more, relative to the total mass of the raw material containing the plastic.

[0087] -Other Components- There are no particular restrictions on other components contained in raw materials containing plastics, and they can be appropriately selected depending on the purpose. Examples include other plastics other than polyolefins, aromatic plastics, and chlorine-containing plastics; and materials that are normally found in waste plastics such as paper and metal. These may be contained individually or in combination of two or more types.

[0088] Other plastics are not particularly limited and can be selected as appropriate depending on the purpose, and examples include polyamide, polyurethane, and polymethyl methacrylate.

[0089] There are no particular restrictions on the yield of other components in the raw material containing plastic, and they can be appropriately selected depending on the type of raw material containing plastic used. However, from the viewpoint of the yield of the active ingredient, it is preferable that it be less than 30% by mass, more preferably 25% by mass or less, and even more preferably 20% by mass or less, based on the total mass of the raw material containing plastic.

[0090] From the viewpoint of reducing environmental impact, it is preferable that the raw materials containing plastic include waste plastic. When the raw materials containing plastic are waste plastic, there are no particular restrictions on the composition and composition ratio, and they can be appropriately selected according to the purpose, but it is preferable that PE is 10% to 40% by mass, PP is 20% to 40% by mass, PS is 10% to 30% by mass, and PET is 1% to 30% by mass.

[0091] As waste plastics, for example, Refuse-derived paper and plastics-densified fuel (RPF) can be used.

[0092] The structure and yield of each component contained in raw materials including plastics can be determined by analysis using methods such as Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), ion chromatography (IC), nuclear magnetic resonance (NMR), liquid chromatography-mass spectrometry (LC-MS), pyrolysis gas chromatography-mass spectrometry (PyGC-MS), and matrix-assisted laser desorption / ionization time-of-flight mass spectrometry (MALDI-TOFMS).

[0093] In the thermal decomposition process S1, there are no particular restrictions on the state of the plastic in the raw materials supplied to the reaction chamber, such as crystalline, glassy, ​​rubbery, or liquid. The plastic may also be in the form of decomposed products. Among these, rubbery or liquid plastic is preferred because it is easier to control the supply amount.

[0094] When the plastic is crystalline or glassy, ​​there are no particular restrictions on its form, and examples include crushed plastic, pellets of crushed plastic, and chips of crushed plastic.

[0095] There are no particular restrictions on the type of plastic used for the pulverized material; it can be appropriately selected depending on the purpose, for example, in powder or flake form.

[0096] Rubber-like or liquid plastic refers to plastic that is fluid at a temperature above its melting point but below its thermal decomposition temperature. Rubber-like or liquid plastic is also called "molten plastic."

[0097] Plastic decomposition products are materials that have been broken down from plastics into smaller molecules, but their molecular weight is still larger than that of the final chemical product.

[0098] The molecular weight of rubbery or liquid plastics does not change from the molecular weight of crystalline or glassy plastics of the same composition. Therefore, plastics and their decomposition products can be distinguished by their molecular weight. As the molecular weight decreases due to decomposition, the melting point also decreases, so in practice, this can be determined by the melting temperature. The melting temperature is measured by the method specified in JIS K7121-2012.

[0099] There are no particular restrictions on the melting temperature of the plastic, and it can be appropriately selected depending on the raw materials used, but 80°C to 200°C is preferred, and 90°C to 190°C is more preferred.

[0100] These raw materials, including various forms of plastic, may be used after being processed separately from the chemical manufacturing methods of this disclosure, or after being subjected to other processing as described below.

[0101] <Other Processing> The method for producing the chemical product of this disclosure may further include, as necessary, pre-treating the raw materials containing plastic, supplying the raw materials containing plastic to the reaction section, supplying the raw materials containing plastic to the reaction section, thermal decomposition, recovering the chemical product obtained in S1, post-treating the chemical product, and separating the useful components in the chemical product.

[0102] Figure 2 shows another example of a flowchart of the method for producing the chemicals of this disclosure.

[0103] <<Pre-treatment S11>> In pre-treatment S11, the raw material containing plastic is pre-treated before being subjected to thermal decomposition S1. By pre-treating the raw material containing plastic to make it easier to decompose, the plastic can be decomposed more efficiently. Pre-treatment S11 is performed before thermal decomposition S1, preferably before supplying S12.

[0104] Examples of pretreatment include crushing of raw materials containing plastic, pelletizing (chipping) of crushed raw materials containing plastic, melting of raw materials containing plastic, and pre-decomposition of raw materials containing plastic.

[0105] There are no particular restrictions on the pulverization process of raw materials containing plastic, and one method is to pulverize the raw materials containing plastic using a known pulverizer. There are no particular restrictions on the pulverized material of the raw materials containing plastic, and can be appropriately selected depending on the purpose, for example, in the form of powder or flakes.

[0106] There are no particular restrictions on the method for pelletizing (chipping) pulverized raw materials, including plastics. A suitable method can be selected from conventionally known methods. For example, one method involves melting and extruding the pulverized material, and then cutting the strand-shaped melted extruded material to obtain chipped raw materials.

[0107] There are no particular restrictions on the melting treatment of raw materials containing plastics, and any conventionally known method can be appropriately selected. For example, a method of continuously supplying the material to the decomposition process using a melt extruder can be used. It is preferable to perform the melting treatment of raw materials containing plastics at a temperature of less than 300°C.

[0108] There are no particular limitations on the pre-decomposition treatment of the plastic-containing raw material, but one example is treatment at a temperature above the decomposition temperature of the plastic (for example, above 200°C) but below 300°C. By pre-decomposing the plastic-containing raw material, it is possible to obtain partially decomposed plastic products from the plastic-containing raw material, although their molecular weight is higher than that of the chemicals described herein.

[0109] <<Supplying S12>> In supplying S12, the raw materials containing the plastic that will be heated in the reaction section in thermal decomposition S1 are supplied to the reaction section.

[0110] There are no particular restrictions on the method of supplying the raw materials containing plastic to the reaction section; they may be supplied intermittently or continuously. Among these methods, continuous supply is preferred because it minimizes temperature changes in the heated filler or fluid material.

[0111] When raw materials containing plastic are supplied intermittently to the reaction section, there are no particular restrictions on the supply time, non-supply time, or intervals between these.

[0112] When supplying raw materials containing plastic to the reaction section intermittently, there is no particular limit on the amount of raw materials containing plastic supplied at one time. When supplying raw materials containing plastic to the reaction section intermittently, from the viewpoint of preventing the temperature of the filler layer or fluid material from dropping too low, it is preferable to add the raw materials containing plastic from the second time onward only after the temperature of the filler layer or fluid material, which had dropped during the previous addition, has recovered to the desired temperature.

[0113] When raw materials containing plastic are continuously supplied to the reaction section, there are no particular restrictions on the amount of raw materials containing plastic that can be supplied.

[0114] <<Recovering Chemicals S13>> In recovering chemicals S13, the chemicals obtained in thermal decomposition S1 are recovered. There are no particular restrictions on the recovery method, and a method can be appropriately selected from known methods depending on the type of chemical obtained. For example, gaseous products can be separated by atmospheric pressure or pressurized distillation, and liquid hydrocarbons can be separated by atmospheric pressure or reduced pressure distillation.

[0115] <<Post-treatment S14>> In post-treatment S14, by-products in the chemicals generated by the thermal decomposition of the raw materials containing plastic in thermal decomposition S1 are decomposed. Post-treatment S14 is performed after thermal decomposition S1, preferably after the recovery of chemicals S13.

[0116] Post-treatment methods performed in S14, which involves post-treatment of chemical products, include, for example, the removal of halogen compounds. Methods for removing halogen compounds include a fixed bed filled with an oxide or hydroxide of one metal selected from alkali metals and alkaline earth metals, or a method of passing an aqueous solution of the oxide or hydroxide of the said metal through the bed.

[0117] <<Separation of useful components S15>> In separation of useful components S15, only the useful components are separated from the chemical product obtained in thermal decomposition S1. Separation of useful components S15 may be performed after thermal decomposition S1, after recovery of chemical product S13, or after post-treatment S14.

[0118] In separating the useful components in S15, there are no particular restrictions on the method for separating the useful components from the by-products, and a method can be appropriately selected from known methods depending on the type of useful component or by-product obtained.

[0119] The chemical manufacturing method described herein suppresses coking and efficiently yields at least one chemical selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons in high yield. The manufactured chemical can be used as a basic chemical suitable for chemical recycling.

[0120] (Chemical Manufacturing Apparatus) The chemical manufacturing apparatus of the present disclosure comprises a reaction section, a raw material supply section connected to the reaction section for supplying raw materials including plastic into the reaction section, a steam supply section connected to the reaction section for supplying steam into the reaction section, and a heating section for heating the reaction section.

[0121] [First Embodiment] In the chemical manufacturing apparatus according to the first embodiment of the present disclosure, the reaction section is a fixed-bed reaction section having a filler layer filled with filler.

[0122] Figure 3 is a schematic cross-sectional view showing an example of a chemical manufacturing apparatus according to the first embodiment of this disclosure.

[0123] The chemical manufacturing apparatus (hereinafter sometimes abbreviated as "manufacturing apparatus 100") comprises a reaction section 1, a filler layer 2a, a raw material supply section 3, a water vapor supply section 4, and a heating section 5. Preferably, the manufacturing apparatus 100 further comprises an inert gas supply section 6.

[0124] <Reaction Section 1> The reaction section 1 is a component having a filler layer 2a filled with filler. In the reaction section 1, the filler layer 2a placed inside the reaction section 1 is heated by the heating section 5, thereby heating the raw material M (hereinafter sometimes abbreviated as "raw material M") containing plastic that is supplied inside the reaction section 1.

[0125] For example, if the inner surface temperature of the reaction section 1 is 700°C or less, the material of the reaction section 1 is alumina (Al ２ O ３ ), Zirconia (ZrO ３ ), silicon carbide (SiC), silicon nitride (Si ３ N ４ ), mullite (3Al ２ O ３ ・2SiO ２ Inorganic compounds such as ) or ceramics thereof; alloys such as stainless steel (e.g., SUS316, SUS316L, SUS310S, etc.), Inconel®, Hastelloy®, etc. can be used.

[0126] For example, if the inner surface temperature of the reaction section 1 is greater than 700°C and less than or equal to 950°C, the material of the reaction section 1 is alumina (Al ２ O ３ ), Zirconia (ZrO ３ ), silicon carbide (SiC), silicon nitride (Si ３ N ４ ), mullite (3Al ２ O ３ ・2SiO ２ Inorganic compounds such as ) or ceramics thereof; alloys such as Inconel® and Hastelloy® can be used.

[0127] The shape, structure, and size of the reaction section 1 are not particularly limited as long as they can accommodate the filler layer 2a and allow the raw material M to flow through them, and can be appropriately selected according to the purpose.

[0128] Examples of the shape of the reaction section 1 include cylindrical, rectangular parallelepiped, conical, frustoconical, and columnar shapes in which the cross-sectional shape perpendicular to the longitudinal direction of the reaction section 1 is polygonal.

[0129] To retain the filler inside the reaction section 1, it is preferable to install a stopper 10 through which water vapor Wv can flow, thereby sealing the inside of the reaction section 1. As the stopper 10, the one described in the section (Method for Manufacturing Chemical Products) of this disclosure can be used.

[0130] <Filler layer 2a> The filler layer 2a is placed in the internal space of the reaction section 1. The filler layer 2a can be the one described in the section (Method of manufacturing chemical products) of this disclosure.

[0131] Figure 4A is a schematic diagram showing an example of a cross-section parallel to the filler deposition direction in the filler layer of the reaction section. Figure 4B is a schematic diagram along the IVB-IVB line in Figure 4A. The reaction section 1 shown in Figures 4A and 4B is cylindrical, and is a cylindrical fixed-bed reaction section with a perfectly circular cross-section perpendicular to the longitudinal direction of the reaction section.

[0132] In the internal space of the reaction section 1, the direction of gravity in which the filler accumulates due to its own weight is defined as the Y-axis direction, the direction approximately perpendicular to the Y-axis direction is defined as the X-axis direction, and the direction approximately perpendicular to both the X-axis and Y-axis directions is defined as the Z-axis direction. The X-axis, Y-axis, and Z-axis are mutually orthogonal. The longitudinal direction of the reaction section 1 is preferably the Y-axis direction, but is not limited to this.

[0133] In this disclosure, "approximately orthogonal" is not limited to 90°, but allows for a difference of 90° ± 5°.

[0134] In this disclosure, the height H of the filler layer 2a is defined as the distance (cm) from the lower end of the portion of the reaction section 1 in which the filler layer 2a is contained to the upper end of the filler layer 2a. For example, when filling a cylindrical reaction section 1 to form a filler layer 2a, a stopper 10 is required to prevent it from falling due to its own weight. In this case, the lower end of the portion of the reaction section 1 in which the filler layer 2a is contained is the portion where the filler layer and the stopper 10 are in contact, and the height from the top of the stopper 10 to the uppermost part where the filler is deposited is the height H of the filler layer 2a. The height H of the filler layer 2a can also be expressed as the depth in the deposition direction of the filler layer 2a or the length in the Y-axis direction.

[0135] <Raw Material Supply Unit 3> The raw material supply unit 3 is connected to the reaction unit 1 and is a component that supplies raw material M, including plastic, into the reaction unit 1. Examples of the raw material supply unit 3 include a raw material distribution unit 3a for circulating the raw material M, including plastic, and a pump 3b.

[0136] The raw material distribution section 3a is a component that connects the storage section 11 and the reaction section 1, and allows the raw material M to pass through its interior.

[0137] Pump 3b is a component that circulates raw material M in a fixed amount for a fixed period of time. A known pump can be used for pump 3b.

[0138] In this disclosure, "connection" of the raw material supply unit 3 to the reaction unit 1 means that the inside of the raw material distribution section 3a of the raw material supply unit 3 and the inside of the reaction unit 1 are in communication so that the raw material M can pass through them.

[0139] There are no particular restrictions on the material of the raw material supply unit 3; for example, it can be appropriately selected from the same materials as those used for the reaction unit 1, depending on the purpose.

[0140] The shape, structure, and size of the raw material distribution section 3a of the raw material supply section 3 are not particularly limited as long as it can be connected to the reaction section 1 and supply the raw material M to the reaction section 1. They can be appropriately selected according to the purpose, for example, a cylindrical shape or a rectangular parallelepiped. Also, if a part of the reaction section 1 has an opening, this opening can be used as the raw material supply section 3.

[0141] The location of the raw material supply unit 3 is not particularly limited, as long as it can be connected to the reaction unit 1 and can supply raw materials M, including plastic, into the reaction unit 1. It can be appropriately selected depending on the type of raw material M. Figure 3 shows the raw material supply unit 3 positioned on the upper surface in the longitudinal direction of the reaction unit 1, but it may also be positioned on the side of the reaction unit 1.

[0142] The raw material M containing plastic used in the manufacturing apparatus 100 is as described in the section (Method for producing the compound) of this disclosure.

[0143] <Steam Supply Unit 4> The steam supply unit 4 is connected to the reaction unit 1 and is a component that supplies steam Wv into the inside of the reaction unit 1. Examples of the steam supply unit 4 include a water supply unit 4a, a steam vaporization unit 4b, a pump 4c, a water flow unit 4d, and a steam flow unit 4e.

[0144] The water supply section 4a is a component that contains water W, which is the raw material for water vapor Wv.

[0145] The water vaporization section 4b is a component that vaporizes water W into water vapor. The water vaporization section 4b is not particularly limited as long as it can vaporize water W into water vapor Wv, and examples include a copper pipe through which water W passes and a heater (for example, a mantle heater) that heats the copper pipe.

[0146] Pump 4c is a component that circulates water vapor Wv in a constant amount for a constant period of time. A known pump can be used for pump 4c.

[0147] The water flow section 4d is a component that connects the water supply section 4a and the water vaporization section 4b, and allows water to pass through its interior.

[0148] The water vapor circulation section 4e is a component that connects the water vaporization section 4b and the reaction section 1, and allows water vapor Wv to pass through its interior.

[0149] In this disclosure, "connection" between the water vapor vaporization section 4b and the reaction section 1 means that the inside of the water vapor flow section 4e of the water vapor supply section 4 and the inside of the reaction section 1 are in communication with the reaction section 1 so that water vapor Wv can pass through them.

[0150] There are no particular restrictions on the material of the steam supply unit 4; for example, it can be appropriately selected from the same materials as the reaction unit 1, depending on the purpose.

[0151] When the manufacturing apparatus 100 is in operation, it is preferable that the steam supply unit 4 be positioned such that the direction of steam Wv supply is the same as the direction of raw material M supply. In Figure 3, the steam flow section 4e of the steam supply unit 4 is shown to be positioned on the upper surface in the longitudinal direction of the reaction unit 1, but it may also be positioned on the side of the reaction unit 1.

[0152] <Heating section 5> The heating section 5 is a component that heats the reaction section 1. There are no particular restrictions on the heating section 5; it may be an external heating method that heats the fluidized bed by heat transfer from the outside, or an internal heating method that generates heat in the filler layer 2a itself. For the external heating method, a known electric furnace can be used as the heating section 5. For the internal heating method, a resistance heating method can be used, for example, in which two electrodes are attached to the reaction section 1 in contact with each other, and heat is generated by applying a voltage between the electrodes.

[0153] The temperature of the reaction section 1 can be measured by inserting a thermocouple into the center of the filler layer 2a.

[0154] <Inert Gas Supply Unit 6> The inert gas supply unit 6 is a component connected to the reaction unit 1 and supplies inert gas G into the reaction unit 1. Examples of the inert gas supply unit 6 include an inert gas flow unit 6a through which the inert gas G flows, and a pump 6b that flows the inert gas G in a fixed amount for a fixed period of time.

[0155] In this disclosure, "connecting" the inert gas supply unit 6 to the reaction unit 1 means that the inside of the inert gas flow section 6a of the inert gas supply unit 6 and the inside of the reaction unit 1 are in communication with the reaction unit 1 so that the inert gas G can pass through them.

[0156] There are no particular restrictions on the material of the inert gas supply unit 6; for example, it can be appropriately selected from the same materials as the reaction unit 1, depending on the purpose.

[0157] The shape, structure, and size of the inert gas supply unit 6 are not particularly limited as long as it can be connected to the reaction unit 1 and supply inert gas G to the reaction unit 1. They can be appropriately selected according to the purpose, for example, a cylindrical shape or a rectangular parallelepiped. Also, if a part of the reaction unit 1 has an opening, this opening can be used as the inert gas supply unit 6.

[0158] When the manufacturing apparatus 100 is in operation, it is preferable that the inert gas supply unit 6 be positioned such that the direction of supply of the inert gas G is the same as the direction of supply of the raw material M. In Figure 3, the inert gas supply unit 6 is shown to be positioned on the upper surface in the longitudinal direction of the reaction unit 1, but it may also be positioned on the side of the reaction unit 1.

[0159] As for the type of inert gas G, those described in the section (Method of Manufacturing Chemical Products) of this disclosure can be used.

[0160] <Other Components> Other components are not particularly limited as long as they do not impair the effectiveness of the chemical manufacturing apparatus according to the first embodiment of this disclosure. Examples include a chemical recovery unit 7, a chemical removal unit 8, a cooling unit 9, a stopper 10, a storage unit 11, a three-way cock 12, an exhaust unit 13, a mist trap 14, a hydrogen chloride trap 15a, a measuring unit for measuring the yield of useful components, a pre-processing unit, a post-processing unit, a separation unit, and the like.

[0161] <<Recovery Unit 7>> The recovery unit 7 is a component that recovers chemical products R generated from raw materials M, including plastic. The recovery unit 7 may consist of only one unit or two or more units.

[0162] There are no particular restrictions on the structure, shape, material, and size of the recovery section 7, and they can be appropriately selected according to the purpose and type of product, including known containers.

[0163] Furthermore, the recovery unit 7 may contain a solvent capable of separating the useful components. There are no particular restrictions on the solvent, and it can be appropriately selected depending on the type of useful component to be recovered. For example, ethanol, hexane, dimethylformamide, cyclopentane, and water can be used as solvents for extracting useful components from liquid products.

[0164] The useful components in the gaseous product can be suitably separated by further pressurized distillation.

[0165] <<Removal Section 8>> The removal section 8 is a component that removes the chemical product R generated from the raw material M containing plastic from the reaction section 1. Preferably, the removal section 8 connects the reaction section 1 and the recovery section 7. If the manufacturing apparatus 100 has other components between the reaction section 1 and the recovery section 7, the removal section 8 may be located in the region connecting the reaction section 1 and the other components, and in the region connecting the other components and the recovery section 7. In other words, there may be one removal section 8 or there may be multiple removal sections 8.

[0166] Figure 3 shows, but is not limited to, an outlet 8a connecting the reaction section 1 and the three-way stopcock 12, an outlet 8b connecting the three-way stopcock 12 and the cooling section 9, an outlet 8c connecting the cooling section 9 and the mist trap 14, an outlet 8d connecting the mist trap 14 and the hydrogen chloride trap 15a, and an outlet 8e connecting the hydrogen chloride trap 15a and the recovery section 7.

[0167] In this disclosure, "connection" of the extraction unit 8 to the reaction unit 1, the recovery unit 7, and other various components means that the inside of the extraction unit 8 and the inside of the reaction unit 1, the recovery unit 7, or other various components are in communication so that the chemical product R can pass through them.

[0168] There are no particular restrictions on the material of the extraction section 8; for example, it can be appropriately selected from the same materials as the reaction section 1, depending on the purpose.

[0169] The shape, structure, and size of the extraction section 8 are not particularly limited as long as they can extract the chemical product R processed in the reaction section 1, and can be appropriately selected according to the purpose. Examples include cylindrical shapes and rectangular parallelepipeds. Furthermore, if a part of the reaction section 1 has an opening, this opening can also be used as the extraction section 8.

[0170] <<Cooling Section 9>> The cooling section 9 is a component that cools the chemical product R obtained after passing through the reaction section 1. By cooling the chemical product R, the liquid component in the product can be recovered within the cooling section.

[0171] The cooling unit 9 is preferably positioned between the extraction unit 8 and the recovery unit 7. That is, the cooling unit 9 is preferably connected to the extraction unit 8 in one part and to the recovery unit 7 in another part.

[0172] In this disclosure, "connection" of the cooling unit 9 to the extraction unit 8 means that the interior of the cooling unit 9 and the interior of the extraction unit 8 are in communication so that the chemical product R can pass through them. Furthermore, "connection" of the cooling unit 9 to the recovery unit 7 means that the interior of the cooling unit 9 and the interior of the recovery unit 7 are in communication so that the chemical product R can pass through them.

[0173] Examples of the cooling section 9 include a cooling trap 9a for cooling the chemical product R, and a cooling section 9b for cooling the cooling trap 9a. The structure, shape, material, and size of the cooling trap 9a and the cooling section 9b are not particularly limited as long as they can cool the chemical product R, and can be appropriately selected according to the purpose.

[0174] The cooling trap 9a may contain an organic solvent 9c for dissolving the chemical R. The organic solvent 9c can condense the useful components in the chemical R, especially the liquid useful components. A non-aqueous solvent is preferred as the organic solvent for dissolving the chemical R. Examples of non-aqueous solvents include aromatic organic solvents such as monochlorobenzene, o-dichlorobenzene, and mesitylene. It is preferable that the outlet of the outlet section 8b is placed in the organic solvent 9c so that the chemical R (e.g., the generated gas) bubbles in the organic solvent 9c.

[0175] The useful components dissolved in a non-aqueous solvent can be suitably separated by further distillation at atmospheric pressure.

[0176] The cooling section 9b is not particularly limited as long as it can cool the cooling trap 9a, and may, for example, contain a refrigerant 9d. Examples of refrigerant 9d include ice water.

[0177] <<Stopper 10>> The stopper 10 is placed inside the reaction section 1 and is a component that seals the reaction section 1 to prevent the filler from falling in. However, the stopper 10 is a component that does not allow the filler to pass through, but allows water vapor Wv, raw material M, or chemical product R to pass through.

[0178] The structure, shape, material, and size of the stopper 10 are not particularly limited, as long as they do not allow filler to pass through and allow water vapor Wv, raw material M, or chemical R to be added. They can be appropriately selected according to the purpose, for example, quartz wool or a sieve. These may be used individually or in combination of two or more types.

[0179] <<Storage section 11>> The storage section 11 is a component for storing raw materials M, including plastic.

[0180] The structure, shape, material, and size of the storage section 11 are not particularly limited as long as it can store raw materials M including plastic, and can be appropriately selected according to the purpose.

[0181] There are no particular restrictions on the number of storage units 11; there may be one or more. If the manufacturing apparatus 100 has multiple storage units 11, for example, it can be used to store plastics containing polyolefin and at least one selected from the group consisting of aromatic plastics and chlorine-containing plastics, where the composition and yield of each component differ.

[0182] <<Three-way cock 12>> The three-way cock 12 is positioned between multiple outlets 8, between an outlet 8 and an exhaust outlet 13, etc., and is a component that switches the flow path of exhaust gas, chemicals R, etc.

[0183] There are no particular restrictions on the material and size of the three-way stopcock 12; they can be appropriately selected from known materials depending on the purpose.

[0184] <<Exhaust section 13>> The exhaust section 13 is a component that exhausts the water vapor Wv that has passed through the reaction section 1. If the manufacturing apparatus 100 has an inert gas supply section 6, the exhaust section 13 exhausts the water vapor Wv and inert gas G that have passed through the reaction section 1. The exhaust section 13 is connected via a three-way cock 12 to an outlet section 8, preferably an outlet section 8a connected to the reaction section 1.

[0185] It is preferable that the manufacturing apparatus 100 maintains a water vapor Wv atmosphere in the reaction section 1 before starting the thermal decomposition of the raw material M. Therefore, when supplying only water vapor Wv to the reaction section 1 before starting the thermal decomposition of the raw material M, it is preferable to connect the three-way stopcock 12 to the reaction section 1 and the exhaust section 13, and exhaust the water vapor Wv from the exhaust section 13, in order to avoid the water vapor Wv being recovered in the recovery section 7.

[0186] <<Mist Trap 14>> The mist trap 14 is a component that recovers liquid components that could not be collected by the cooling trap 9a. There are no particular restrictions on the structure, shape, material, and size of the mist trap 14, and they can be appropriately selected according to the purpose.

[0187] <<Hydrogen Chloride Trap 15a>> The hydrogen chloride trap 15a is a component for separating and recovering hydrogen chloride generated from chlorine-containing plastics, and is preferably installed when the raw material M contains chlorine-containing plastics such as PVC. The hydrogen chloride trap 15a contains a chemical agent 15b. The chemical agent 15b can separate and recover hydrogen chloride encompassed in the chemical product R. Examples of chemical agent 15b include alkaline aqueous solutions such as sodium hydroxide aqueous solution, alkali metal carbonates such as potassium carbonate, and alkaline earth metal carbonates such as calcium carbonate. It is preferable that the outlet of the outlet section 8c is placed in the chemical agent 15b, so that the chemical product R (for example, the generated gas) bubbles in the chemical agent 15b.

[0188] <<Measurement Unit>> The measurement unit is a component that measures the yield of useful components contained in the chemical product R manufactured by the manufacturing apparatus 100.

[0189] The measuring unit may be located inside the manufacturing apparatus 100, or it may be connected to and provided outside the manufacturing apparatus 100.

[0190] The measuring unit is not particularly limited as long as it can measure the yield of useful components contained in the chemical product R, and any known measuring device may be used. Examples of known measuring devices include flame ionization detectors (FIDs) and gas chromatography equipped with thermal conduction detectors (TCDs).

[0191] There are no particular restrictions on the structure, shape, material, and size of the measuring section; they can be appropriately selected according to the purpose and type of product.

[0192] <<Pre-processing section>> The pre-processing section is a component that pre-processes the raw material M, which includes plastic. It is preferable that the pre-processing section is connected to the raw material supply section 3.

[0193] In this disclosure, "connecting" the pre-processing unit to the raw material supply unit 3 means that the inside of the pre-processing unit and the inside of the raw material supply unit 3 are in communication so that the raw material M can pass through them.

[0194] The pre-processing unit performs, for example, the task of transforming the plastic contained in the raw material M into a form or state that is easily decomposed.

[0195] There are no particular restrictions on the material of the pre-treatment section; for example, it can be appropriately selected from the same materials as those used for the reaction section 1, depending on the purpose.

[0196] The shape, structure, and size of the pre-processing unit are not particularly limited as long as it can be connected to the raw material supply unit 3 and perform pre-processing of the raw material M. They can be appropriately selected according to the purpose, and examples include cylindrical and rectangular parallelepiped shapes.

[0197] <<Post-processing section>> The post-processing section is a component that decomposes unwanted components such as by-products from the chemical product R. It is preferable that the post-processing section is connected to the recovery section 7.

[0198] In this disclosure, "connection" of the post-processing unit to the recovery unit 7 means that the inside of the post-processing unit and the inside of the recovery unit 7 are in communication so that the chemical product R can pass through them.

[0199] The post-processing unit performs tasks such as removing paraffin, halogens, etc., generated from the plastic contained in the raw material M.

[0200] There are no particular restrictions on the material of the post-processing section; for example, it can be appropriately selected from the same materials as those used for the reaction section 1, depending on the purpose.

[0201] The shape, structure, and size of the post-processing unit are not particularly limited as long as it can be connected to the recovery unit 7 and decompose unwanted components in the chemical product R. They can be appropriately selected according to the purpose, for example, cylindrical or rectangular.

[0202] <<Separation Processing Unit>> The separation processing unit is a component that separates useful components from the chemical product R recovered in the recovery unit 7. It is preferable that the separation processing unit is connected to the recovery unit 7 or the post-processing unit.

[0203] In this disclosure, "connection" of the separation processing unit to the recovery unit 7 or post-processing unit means that the interior of the post-separation processing unit and the interior of the recovery unit 7 or post-processing unit are in communication with each other in a manner that allows the chemical product R to pass through.

[0204] There are no particular restrictions on the material of the separation processing unit; for example, it can be appropriately selected from the same materials as those used for the reaction unit 1, depending on the purpose.

[0205] The shape, structure, and size of the separation processing unit are not particularly limited as long as it can be connected to the recovery unit 7 or the post-processing unit and separate useful components from the chemical product R. They can be appropriately selected according to the purpose, for example, a cylindrical shape or a rectangular parallelepiped.

[0206] The separation unit includes, for example, a pressurized distillation apparatus. This separates the useful components from the chemical product R. For example, if the chemical product R contains at least one chemical selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons, these useful components can be suitably separated from the chemical product R by pressurized distillation.

[0207] Next, a specific example of the operation of the chemical manufacturing apparatus 100 according to the first embodiment will be described. In the manufacturing apparatus 100, for example, the heating unit 5 heats the reaction unit 1 to a desired temperature. At this time, the filler layer 2a is heated to a desired temperature. Then, while the reaction unit 1 is heated by the heating unit 5, steam Wv is supplied to the reaction unit 1 from the steam supply unit 4, and raw material M containing plastic stored in the storage unit 11 is supplied to the filler layer 2a of the reaction unit 1 by the raw material supply unit 3, thereby performing the supplying S12 and thermal decomposition S1 in the compound manufacturing method of this disclosure. At this time, the amount of steam Wv supplied to the reaction unit 1 is adjusted by the pump 4c. The amount of raw material M supplied to the reaction unit 1 is adjusted by the pump 3b.

[0208] If the manufacturing apparatus 100 has an inert gas supply unit 6, water vapor Wv is supplied to the reaction unit 1 from the water vapor supply unit 4, and an inert gas G other than water vapor is supplied from the inert gas supply unit 6. At this time, the amount of inert gas G supplied to the reaction unit 1 is adjusted by the pump 6b.

[0209] The raw material M and water vapor Wv may be mixed before being supplied to the reaction section 1. The raw material M and inert gas G may also be mixed before being supplied to the reaction section 1. By mixing the raw material M, water vapor Wv, and optionally the inert gas G before being supplied to the reaction section 1, the raw material M can be supplied to the reaction section 1 in accordance with the flow of water vapor Wv and the inert gas G. Furthermore, by mixing the water vapor Wv and the inert gas G before being supplied to the reaction section 1, the raw material M can be supplied to the reaction section 1 based on the combined flow rate of the water vapor Wv and the inert gas G.

[0210] In the steam supply section 4, water W in the water supply section 4a passes through the water flow section 4d and is supplied to the steam vaporization section 4b. In the steam vaporization section 4b, the water W vaporizes due to heat and becomes steam Wv. The steam Wv passes through the steam flow section 4e and is supplied to the reaction section 1.

[0211] The chemical product R, which is a product containing useful components obtained by thermal decomposition of raw material M, can be recovered in the cooling unit 9 and the recovery unit 7, and optionally in the mist trap 14, as described in S13 in the method for producing the compound of this disclosure. Subsequently, post-processing in the method for producing the compound of this disclosure may be performed in the post-processing unit S14, or the useful components in the method for producing the compound of this disclosure may be separated in the separation unit S15.

[0212] The chemical product R containing useful components obtained by thermal decomposition of raw material M is recovered in the recovery unit 7. Preferably, the chemical product R containing useful components obtained by thermal decomposition of raw material M is removed from the reaction unit 1 by the removal unit 8a, passes through the removal unit 8b, goes through the cooling unit 9, then passes through the removal unit 8c, mist trap 14, removal unit 8d, hydrogen chloride trap 15a, and removal unit 8e in that order, and is then recovered in the recovery unit 7. In the recovery unit 7, preferably the removal unit 8, cooling unit 9, mist trap 14, hydrogen chloride trap 15a, and recovery unit 7, the chemical product in the method for producing the compound of this disclosure can be recovered (S13).

[0213] When chemical product R is transferred to the cooling trap 9a of the cooling unit 9, first, chemical product R is cooled in the cooling unit 9, which contains organic solvent 9c cooled by the refrigerant 9d in the insulation unit 9b. As a result, components in chemical product R that can dissolve in the organic solvent 9c are condensed in the organic solvent 9c. On the other hand, components in chemical product R that do not dissolve in the organic solvent 9c are transferred directly to the recovery unit 7. This allows the target components to be recovered in the organic solvent 9c and in the recovery unit 7.

[0214] If necessary, the raw material M is subjected to a pre-treatment process S11 before being supplied to the reaction unit 1, thereby performing the pre-treatment in the method for producing the compound of this disclosure. The chemical product R recovered in the recovery unit 7 is subjected to a post-treatment process S14, thereby performing the post-treatment in the method for producing the compound of this disclosure. The chemical product R recovered in the recovery unit 7, or the chemical product R from which unwanted components have been decomposed in the post-treatment process, is subjected to a separation process S15, thereby separating the useful components in the method for producing the compound of this disclosure.

[0215] The chemical manufacturing apparatus according to the first embodiment described above can suppress coking and efficiently produce at least one chemical selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons in high yield. The manufactured chemical can be used as a basic chemical suitable for chemical recycling.

[0216] Furthermore, various processes in the chemical manufacturing apparatus, such as the timing and speed of supplying raw material M by the raw material supply unit 3, the timing and speed of supplying water vapor Wv by the water vapor supply unit 4, the timing and speed of supplying inert gas G by the inert gas supply unit 6, and the timing, heating temperature, and heating time of heating the reaction unit 1, raw material M, and filler layer 2a by the heating unit 5, are performed by processing signals to each unit by the signal processing unit. The signal processing unit is an electronic circuit such as a CPU, FPGA, or ASIC, and performs the various processes described in the operating method of the chemical manufacturing apparatus of this disclosure by executing instruction codes stored in memory or by designing the circuit for special applications.

[0217] The chemical product R produced by the manufacturing apparatus 100 of this disclosure is as described in the section (Method for producing the compound) of this disclosure.

[0218] [Second Embodiment] In the chemical manufacturing apparatus according to the second embodiment of the present disclosure, the reaction section contains a fluidized material, and the steam supply section is connected to one end of the reaction section and is arranged to supply steam to the fluidized material from a direction opposite to the direction of gravity.

[0219] The chemical manufacturing apparatus according to the second embodiment of this disclosure differs from the chemical manufacturing apparatus according to the first embodiment of this disclosure in that the reaction section is a fluidized bed reaction section. The following describes the differences between the chemical manufacturing apparatus according to the second embodiment of this disclosure and the chemical manufacturing apparatus according to the first embodiment of this disclosure.

[0220] Figure 5 is a schematic cross-sectional view showing an example of a chemical manufacturing apparatus according to the second embodiment of this disclosure.

[0221] The chemical manufacturing apparatus (manufacturing apparatus 100) comprises a reaction section 1, a fluidizing agent 2b, a raw material supply section 3, a steam supply section 4, and a heating section 5. Preferably, the manufacturing apparatus 100 further comprises an inert gas supply section 6.

[0222] <Reaction Unit 1> The reaction unit 1 is a component that houses a fluid material 2b inside. In the reaction unit 1, the fluid material 2b placed inside the reaction unit 1 is heated by the heating unit 5, thereby heating the raw material M containing plastic supplied inside the reaction unit 1.

[0223] The shape, structure, and size of the reaction section 1 are not particularly limited as long as they can accommodate the fluid material 2b and allow the raw material M to flow through them. They can be appropriately selected according to the purpose, but a shape, structure, and size in which the flow direction of the raw material, including plastic, is in the longitudinal direction is preferred.

[0224] Examples of the shape of the reaction section 1 include cylindrical, rectangular parallelepiped, conical, frustoconical, and columnar shapes in which the cross-sectional shape perpendicular to the longitudinal direction of the reaction section 1 is polygonal.

[0225] In order to retain the fluid material 2b inside the reaction section 1, it is preferable to install a stopper 10 that allows water vapor Wv, such as quartz wool, to flow through, thereby sealing the inside of the reaction section 1.

[0226] <Flowing material 2b> The flowing material 2b is placed in the internal space of the reaction section 1. The flowing material 2b can be the one described in the section (Method for manufacturing chemical products) of this disclosure.

[0227] When the manufacturing apparatus 100 is not in operation, the fluid material 2b normally accumulates in the internal space of the reaction section 1 due to its own weight. That is, the direction of accumulation of the fluid material 2b is in the direction of gravity.

[0228] <Steam Supply Unit 4> When the manufacturing apparatus 100 is in operation, it is preferable that the fluid material 2b flows by at least steam Wv. In order to make the fluid material 2b flow by steam Wv, it is preferable to arrange the steam supply unit 4 so as to supply steam Wv to the fluid material 2b from the opposite direction to the direction of gravity in the internal space of the reaction unit 1, and it is more preferable that the steam supply unit 4 be located below the position where the fluid material 2b is placed in the reaction unit 1 in the direction of gravity. In Figure 5, the steam supply unit 4 is shown to be located on the lower surface in the longitudinal direction of the reaction unit 1, but it may also be located on the side of the reaction unit 1.

[0229] <Inert Gas Supply Unit 6> When an inert gas G other than water vapor Wv is used during the operation of the manufacturing apparatus 100, it is preferable that the fluid material 2b flows with a mixed gas of water vapor Wv and inert gas G. In order to make the fluid material 2b flow with a mixed gas of water vapor Wv and inert gas G, it is preferable to arrange the inert gas supply unit 6 so as to supply the inert gas G to the fluid material 2b from the direction opposite to the direction of gravity in the internal space of the reaction unit 1, and it is even more preferable that the inert gas supply unit 6 be positioned below the position where the fluid material 2b is placed in the reaction unit 1 in the direction of gravity. In Figure 5, the inert gas supply unit 6 is shown to be positioned on the lower surface in the longitudinal direction of the reaction unit 1, but it may also be positioned on the side of the reaction unit 1.

[0230] <Other Components> Other components similar to those used in the chemical manufacturing apparatus according to the first embodiment of this disclosure can also be used, but it is more preferable that the chemical R extraction section 8 be positioned above the position where the fluid material 2b is placed in the direction of gravity.

[0231] Next, a specific example of the operation of the chemical manufacturing apparatus 100 according to the second embodiment will be described. In the manufacturing apparatus 100, for example, the heating unit 5 heats the reaction unit 1 to a desired temperature. At this time, the fluid material 2b is heated to a desired temperature. Then, while the reaction unit 1 is heated by the heating unit 5, at least steam Wv is supplied to the reaction unit 1 from the steam supply unit 4, and with the fluid material 2b in a fluidized state, the raw material M containing plastic stored in the storage unit 11 is supplied to the fluidized fluid material 2b in the reaction unit 1 by the raw material supply unit 3, thereby performing the supply S12 and thermal decomposition S1 in the compound manufacturing method of this disclosure.

[0232] If the manufacturing apparatus 100 has an inert gas supply unit 6, water vapor Wv is supplied to the reaction unit 1 from the water vapor supply unit 4, and an inert gas G other than water vapor is supplied from the inert gas supply unit 6. In this case, it is preferable that the water vapor Wv and the inert gas G are mixed before being supplied to the reaction unit 1. This allows the fluid material 2b to be fluidized by the total flow rate of the water vapor Wv and the inert gas G.

[0233] The chemical manufacturing apparatus according to the second embodiment described above can suppress coking and efficiently produce at least one chemical selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons in high yield. The manufactured chemical can be used as a basic chemical suitable for chemical recycling.

[0234] The embodiments will be described in more detail below with reference to preparation examples, examples, and comparative examples, but the embodiments are not limited to these preparation examples, examples, and comparative examples.

[0235] (Preparation Example 1) <Preparation of Waste Plastic Simulated Pellets> Waste plastic simulated pellets were prepared using the following composition and proportions. Of the raw materials listed below, all raw materials except cellulose were selected from waste plastics and impurities. The prepared waste plastic simulated pellets may be referred to as "RPF" below. [Composition and proportions] ・Polyethylene … 27% by mass ・Polypropylene … 27% by mass ・Polystyrene … 19% by mass ・Polyethylene terephthalate … 14% by mass ・Polyvinyl chloride … 2% by mass ・Cellulose … 5% by mass (Cellulose powder, manufactured by MP Biomedicals, LLC) ・Metallic aluminum … 2% by mass ・Calcium carbonate … 2% by mass ・Polyamide … 2% by mass (Total … 100% by mass)

[0236] (Example 1) <Preparation of the apparatus> The manufacturing apparatus 100 shown in Figures 3, 4A, and 4B was prepared. Specifically, a drain plate was placed in a cylindrical quartz tube with an inner diameter of 15 mm and a height of 550 mm, quartz wool was laid down and a stopper 10 was placed in it, and silica gel particles as filler (product name: CARiACT Q-10, particle size: 1.18 mm to 2.36 mm, manufactured by Fuji Silicia Chemical Co., Ltd.) were filled in so that the filler height H was 6 cm, forming a reaction section 1 having a filler layer 2a. 5 g of silica gel particles were used. The quartz tube was set in a cylindrical electric furnace (product name: ARF-30MC, manufactured by Asahi Rika Seisakusho) installed vertically. The electric furnace is an external heating type heating section 5. A Y-shaped connecting pipe (model number CY1938, manufactured by AS ONE Corporation) was connected to the top (inlet) of the quartz tube. A manual powder feeding device (airless feed cock, manufactured by Asahi Seisakusho Co., Ltd.) as the raw material supply unit 3 and a gas inlet as the inert gas supply unit 6 were connected to one end of the Y-shaped connecting pipe. A Teflon® bore-through joint (half female joint, model number AF-HMI10RC1 / 4, manufactured by AS ONE Corporation, connected to a bore-through connector, model number 30-3MCT4-C, manufactured by Flowell Co., Ltd.) was connected to the other end of the Y-shaped connecting pipe, which is a 10 mm glass tube. One end of a copper pipe with an outer diameter of approximately 3 mm was connected to the bore-through joint. This copper pipe was wound into a spiral shape with a diameter of approximately 1.5 cm and a length of 20 cm, and covered with a mantle heater to form the water vaporization unit 4b. One end of the copper pipe was connected to one end of a Teflon® union (manufactured by Flowell Co., Ltd., model number 30-8RU 3C), and one end of an 8mm outer diameter silicone tube for liquid supply (water flow section 4d) was connected to the other end of the Teflon® union. The silicone tube for liquid supply, which served as the water flow section 4d, was connected to a peristaltic pump (manufactured by Tokyo Rikakikai Co., Ltd., model number MP-3000), and the other end of the silicone tube for liquid supply was connected to a plastic bottle filled with pure water W, which served as the water supply section 4a. The Y-shaped connecting pipe was covered with a mantle heater and served as the steam preheating section. In the path from the top of the electric furnace to the steam vaporization section 4b, the parts not covered by the mantle heater were insulated by covering them with insulating material.Furthermore, the upper part of a ground-joint connecting tube (with branch and central tubes, manufactured by AS ONE Corporation, model number CL0210-03-10), which serves as an extraction section 8a, was connected to the bottom of the electric furnace, and a pear-shaped flask 16 was connected to the lower part of the ground-joint connecting tube. The outlet of the extraction section 8a was placed inside the pear-shaped flask 16. During the experiment, the pear-shaped flask 16 was cooled using a water bath 17, and the water condensed from the water vapor was collected. In addition, one end of a gas extraction pipe (silicone tube), which serves as an extraction section 8b for extracting the chemical product R, was connected to the branch tube of the ground-joint connecting tube. The other end of the extraction section 8b was connected to a three-way stopcock 12 made of Teflon®, with one end of the three-way stopcock connected to an exhaust section 13 and the other end connected to the extraction section 8b (silicone tube). The other end of the outlet section 8b was connected to the inlet side of a cooling trap 9a containing 15 mL of o-dichlorobenzene (reagent grade, manufactured by Kanto Chemical Co., Ltd.) as the organic solvent 9c. The cooling trap 9a was placed inside the cooling section 9b containing ice water as the refrigerant 9d. One end of the outlet section 8c (silicone tube) was connected to the outlet side of the cooling trap 9a, and the other end of the outlet section 8c was connected to the end of a mist trap 14 filled with quartz wool. One end of the outlet section 8d (silicone tube) was connected to the other end of the mist trap 14, and the other end of the outlet section 8d was connected to the inlet side of a hydrogen chloride trap 15a filled with 15 mL of a 1 mol / L sodium hydroxide aqueous solution (prepared by diluting sodium hydroxide manufactured by Fujifilm Wako Co., Ltd. with pure water) as the chemical agent 15b. One end of another outlet 8e (silicone tube) was connected to the outlet side of the hydrogen chloride trap 15a, and the other end of the outlet 8e was connected to one gas bag (volume 10L) which served as the recovery unit 7. A thermocouple was inserted into the center of the filler layer 2a filled in the quartz tube.

[0237] <Thermal Decomposition S1> Nitrogen gas was blown in from the inert gas supply unit 6 at a flow rate of 1,200 N mL / min until the temperature in the reaction unit 1 reached 800°C, the temperature in the water vaporization unit 4b reached 250°C, and the temperature in the water vapor preheating unit reached 300°C. After the temperatures stabilized, the peristaltic pump 4c was started, and pure water W was supplied at a flow rate equivalent to 400 N mL / min of water vapor Wv. Here, N represents the value converted to 0°C and 1 atmosphere. After supplying the liquid for 5 minutes and confirming that the temperature and pressure in the reaction unit 1 had stabilized, the three-way stopcock 12 was connected to the bottom of the electric furnace and the outlet unit 8b, and the recovery of the reaction product using the cooling trap 9a and two gas bags was started. Immediately after the start of recovery, a total of 3.2 g of the waste plastic simulant pellets (raw material M) prepared in Preparation Example 1 were supplied into the quartz tube from a manual powder input device over a period of 3 minutes under an atmosphere of nitrogen gas at a flow rate of 1,200 N mL / min and water vapor at a flow rate of 400 N mL / min. After the supply of waste plastic simulant pellets was completed, the recovery of chemical product R as a product was continued. Seven minutes after the end of the supply of raw material M, the three-way stopcock 12 was connected to the reaction section 1 and the exhaust section 13, and the gas bag was disconnected from the manufacturing apparatus 100. The cooling trap 9a was left to stand until it reached room temperature (25°C ± 5°C) before being disconnected from the manufacturing apparatus 100. The liquid component of chemical product R was recovered in the cooling trap 9a and the mist trap 14. The gaseous component of chemical product R was recovered in the gas bag.

[0238] Furthermore, the two gas bags were used to collect gas by switching between them as needed, using a three-way valve located midway through the extraction section 8e.

[0239] (Examples 2-4) In Example 1, the decomposition of raw material M was carried out in the same manner as in Example 1, except that the decomposition conditions were changed to the decomposition conditions shown in Table 1, and the liquid and gaseous components as chemical product R were recovered.

[0240] (Comparative Example 1) The raw material M was decomposed in the same manner as in Example 1, except that the decomposition conditions were changed to the decomposition conditions shown in Table 1, and the liquid and gaseous components as chemical product R were recovered.

[0241] (Example 5 and Comparative Example 2) In Example 1, the decomposition of raw material M was carried out in the same manner as in Example 1, except that the decomposition conditions were changed to the decomposition conditions shown in Table 2, and the liquid and gaseous components as chemical product R were recovered.

[0242] (Example 6 and Comparative Example 3) In the same manner as in Example 1, except that the decomposition conditions were changed to the decomposition conditions shown in Table 3, the raw material M was decomposed and the liquid and gaseous components as chemical product R were recovered.

[0243] <<Analysis of Gas Bag Contents>> In Examples 1-6 and Comparative Examples 1-3, the yield (mass%) of useful components and by-products in the pyrolysis gas recovered in the gas bag was determined by the following method.

[0244] In the gas bag, cyclopentane (>98.0%, density 0.75 g / cm³) was used as an internal standard substance. ３ 40 μL of (manufactured by Tokyo Chemical Industry Co., Ltd.) was added. The gas bag was heated to approximately 40°C to completely vaporize the contents, and then the contents were mixed by gently kneading the gas bag. The obtained contents were used as an analytical sample and analyzed by gas chromatography (GC) under the following GC analysis conditions. The proportion of each component relative to carbon atoms in the pyrolysis gas in the gas bag was determined (Cmol%) from the ratio of the peak area of ​​cyclopentane to the peak area of ​​each component. The mass of each component in the pyrolysis gas in the gas bag was calculated from the proportion of each component relative to carbon atoms in the pyrolysis gas in the gas bag (Cmol%) and the amount of cyclopentane added to the gas bag (40 μL), and the yield (mass%) relative to the raw material M was determined. The results are shown in Tables 1 to 3. [GC Analysis Conditions] • Instrument: Nexus 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 volume: 1 mL • Split ratio: 1 / 200 • Column temperature: Held at 120°C for 9 minutes, then increased to 200°C at 10°C / min, and held at 200°C for 30 minutes. • Detector: Flame ionization detector (FID) • Detector temperature: 200°C

[0245] <<Analysis of contents of cooling trap and mist trap>> In Examples 1 to 6 and Comparative Examples 1 to 3, the yield (mass%) of useful components and by-products in the pyrolysis components recovered in the cooling trap 9a and mist trap 14 was determined by the following method.

[0246] The contents of the cooling trap 9a and mist trap 14 were transferred to a sample vial. Two mL of o-dichlorobenzene (reagent grade, manufactured by Kanto Chemical Co., Ltd.) was added to each of the nearly empty cooling trap 9a and mist trap 14 to dissolve the remaining contents, which were then transferred to the sample vial. This process was repeated three times to wash the cooling trap 9a and mist trap 14. Approximately 0.3 g of cyclopentane (>98.0%, manufactured by Tokyo Chemical Industry Co., Ltd.) was weighed and added to the sample vial as an internal standard substance to prepare the analytical sample, which was then analyzed by gas chromatography (GC) under the following GC analysis conditions. The carbon-carbon-based percentage (Cmol%) of each component in the thermal decomposition components in the cooling trap 9a and mist trap 14 was determined from the ratio of the peak area of ​​cyclopentane to the peak area of ​​each component. The mass of each component in the pyrolysis product in cooling trap 9a and mist trap 14 was calculated from the proportion of each component (Cmol%) relative to carbon atoms in the pyrolysis gas in cooling trap 9a and mist trap 14, and the amount of cyclopentane (0.3 g) put into the sample vial, and the yield (mass%) relative to the raw material M was determined. The results are shown in Tables 1 to 3. [GC Analysis Conditions] • Instrument: Nexus 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 Volume: 1 μL • Split Ratio: 1 / 50 • Column Temperature: Temperature increase program set in the following order: 35°C (10 mins) → Increase (5°C / min) → 350°C (10 mins) • Detector: Flame Ionization Detector (FID) • Detector Temperature: 350°C

[0247] <<Calculation of calcination weight loss rate>> In Examples 1 to 6 and Comparative Examples 1 to 3, after the completion of thermal decomposition S1, the filler layer 2 was washed by flowing o-dichlorobenzene (reagent grade, manufactured by Kanto Chemical Co., Ltd.) and acetone (reagent grade, manufactured by Kanto Chemical Co., Ltd.) through a manual powder feeder. Then, the mixture was left to stand for 10 minutes under a nitrogen gas atmosphere at a flow rate of 1,600 N mL / min to remove the o-dichlorobenzene and acetone from the filler layer 2. Subsequently, the quartz tube having the filler layer 2 was calcined at 200°C for 30 minutes under a nitrogen gas atmosphere at a flow rate of 1,600 N mL / min. The mass X after calcination under a nitrogen gas atmosphere was measured. Next, the quartz tube having the filler layer 2 was calcined at 600°C for 30 minutes under an air atmosphere at a flow rate of 500 N mL / min. The mass Y after air calcination was measured. From the measured values, the calcination weight loss rate was calculated based on the following formula, and this value corresponds to the amount of coking. Loss during firing (mass %) = (mass X - mass Y) / mass of raw material M added × 100

[0248] In Tables 1 to 3, "Yield of useful components" refers to the ratio of the mass of each product listed in Tables 1 to 3 to the mass of the waste plastic simulated pellets (raw material M). In addition, in Tables 1 to 3, "Total yield of useful components" refers to the ratio of the mass of olefins having 2 to 5 carbon atoms and useful aromatic hydrocarbons in the product to the mass of the waste plastic simulated pellets (raw material M).

[0249] In Tables 1 to 3, "useful components" refer to carbon-2 olefins (ethylene), carbon-3 olefins (propylene), carbon-4 olefins (trans-2-butene, 1-butene, isobutene, and cis-2-butene, butadiene), carbon-5 olefins (trans-2-pentene, 2-methyl-2-butene, 1-pentene, 2-methyl-1-butene, and cis-2-pentene, isoprene, cyclopentadiene), and useful aromatic hydrocarbons (benzene, toluene, ethylbenzene, three positional isomers of xylene (p-xylene, m-xylene, and o-xylene), and styrene).

[0250] Furthermore, in Tables 1 to 3, the "Ratio of Total Yield of Useful Components [A / B]" refers to the ratio of the total yield (mass%) of the useful components in each example to the total yield (mass%) of the useful components when the water vapor flow rate is 0 mL / min, under the same conditions for the total flow rates of nitrogen gas and water vapor in the examples and comparative examples. Specifically, the "Ratio of Total Yield of Useful Components [A / B]" in Examples 1 to 4 in Table 1 is the ratio of the total yield (mass%) (A) of the useful components in Examples 1 to 4 to the total yield (mass%) (B) of the useful components in Comparative Example 1. The "Ratio of Total Yield of Useful Components [A / B]" in Example 5 in Table 2 is the ratio of the total yield (mass%) (A) of the useful components in Example 5 to the total yield (mass%) (B) of the useful components in Comparative Example 2. The "Ratio of Total Yield of Useful Components [A / B]" in Example 6 in Table 3 is the ratio of the total yield (mass%) (A) of the useful components in Example 6 to the total yield (mass%) (B) of the useful components in Comparative Example 3.

[0251]

[0252]

[0253]

[0254] From comparisons between Examples 1-4 and Comparative Example 1, between Example 5 and Comparative Example 2, and between Example 6 and Comparative Example 3, it was found that carrying out the thermal decomposition S1 under a water vapor atmosphere reduced the calcination loss rate and decreased the amount of coking generated during the thermal decomposition S1. Furthermore, carrying out the thermal decomposition S1 under a water vapor atmosphere improved the total yield of useful components. In particular, the total yield of olefins with 2 and 3 carbon atoms improved.

[0255] As described above, this disclosure has been explained based on specific embodiments and examples, but these embodiments and examples are merely presented as examples, and this disclosure is not limited to the above embodiments and examples. The above embodiments can be implemented in various other forms, and various combinations, omissions, substitutions, additions, modifications, etc., are possible without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents.

[0256] 1…Reaction section 2a…Filler layer 2b…Flowing material 3…Raw material supply section 3a…Raw material distribution section 3b…Pump 4…Steam supply section 4a…Water supply section 4b…Steam vaporization section 4c…Pump 4d…Water distribution section 4e…Steam distribution section 5…Heating section 6…Inert gas supply section 6a…Inert gas distribution section 6b…Pump 7…Recovery section 8, 8a, 8b, 8c, 8d, 8e…Removal section 9…Cooling section 9a…Cooling trap 9b…Insulation section 9c…Organic solvent 9d…Refrigerant 10…Stopper 11…Storage section 12…Three-way cock 13…Exhaust section 14…Mist trap 15a…Hydrogen chloride trap 15b…Chemicals 16…Round-nose flask 17…Water bath 100…Manufacturing equipment M…Raw material R…Chemicals W…Water Wv…Steam G…Inert gas

Claims

1. A method for producing chemical products, characterized by comprising thermally decomposing a raw material containing plastic under a water vapor atmosphere.

2. The method for producing a chemical product according to claim 1, wherein, in the thermal decomposition, the water vapor concentration in the water vapor atmosphere is 10% by volume or more.

3. The method for producing a chemical product according to claim 1 or 2, wherein the thermal decomposition is carried out in a mixed gas atmosphere of water vapor and an inert gas other than water vapor.

4. The method for producing a chemical product according to claim 1 or 2, wherein the thermal decomposition is carried out in a fixed-bed reaction section having a filler layer filled with filler.

5. The method for producing a chemical product according to claim 1 or 2, wherein the thermal decomposition is carried out in a reaction section containing a fluid material, and the method includes supplying at least steam from one end of the reaction section containing the fluid material to cause the fluid material to flow.

6. The method for producing a chemical product according to claim 1 or claim 2, wherein the heating temperature for the thermal decomposition is 600°C or higher and 1,200°C or lower.

7. A method for producing a chemical product according to claim 1 or claim 2, wherein the raw material containing the plastic includes waste plastic.

8. A method for producing a chemical product according to claim 1 or claim 2, wherein the raw material containing the plastic contains 50% by mass or more of polyolefin.

9. The method for producing a chemical product according to claim 1 or claim 2, wherein the chemical product comprises at least one chemical product selected from the group consisting of olefins having 2 to 5 carbon atoms and aromatic hydrocarbons.

10. A chemical manufacturing apparatus comprising: a reaction section; a raw material supply section connected to the reaction section for supplying raw materials including plastic into the reaction section; a steam supply section connected to the reaction section for supplying steam into the reaction section; and a heating section for heating the reaction section.

11. The apparatus for producing chemical products according to claim 10, further comprising an inert gas supply unit connected to the reaction unit and supplying an inert gas other than water vapor to the reaction unit.

12. The apparatus for producing chemical products according to claim 10 or claim 11, wherein the reaction section is a fixed-bed reaction section having a filler layer filled with filler.

13. The chemical manufacturing apparatus according to claim 10, wherein the reaction section contains a fluid material inside, and the steam supply section is connected to one end of the reaction section and is arranged to supply the steam to the fluid material from a direction opposite to the direction of gravity.

Images