JPWO2016147658A1 - Catalyst for decomposing organic substances, method for producing the same, and method for reducing the molecular weight of organic substances - Google Patents

Abstract

An organic substance decomposing catalyst obtained from converter dust, which can sufficiently exhibit the catalytic effect of iron contained in the converter dust, is obtained. At least a part of the outer shell layer (a) containing a calcium compound as a main component is removed from the converter dust, and the iron oxide layer (b) under the outer shell layer (a) is exposed to the dust surface. Preferably, the converter dust is heat-treated in an oxidizing atmosphere to peel at least a part of the outer shell layer (a). When the outer shell layer (a) is removed from the converter dust, the surface area of the iron oxide layer that can function effectively as a catalyst increases, and the converter dust fully exhibits the catalytic effect of the iron oxide contained in the converter dust. To do.

Description

  The present invention relates to a catalyst used for thermally decomposing an organic substance such as waste plastic to reduce its molecular weight (gasification or oil conversion), a method for producing the same, and a method for reducing the molecular weight of an organic substance.

  In recent years, the energy problem has become a major issue, and as one approach to solve this problem, a method of effectively utilizing the amount of heat possessed by an organic substance is considered. In particular, resin waste such as waste plastics has a high calorific value, and may be effectively used as a fuel to replace fossil fuels. However, since resin waste has poor thermal conductivity and takes a long time to increase its temperature, the combustion speed is very slow, and it is difficult to use it as a fuel substitute if it remains solid. Therefore, a method has been considered in which resins are decomposed and converted into gas or oil before being used as fuel. A thermal decomposition method can be used for gasification / oilification of resin waste, but in this method, a catalyst for promoting thermal decomposition is used. As this catalyst, it is known that FCC catalyst mainly composed of zeolite, silica alumina, etc., transition metal catalyst mainly composed of Fe, Ni, etc., noble metal catalyst mainly composed of Pt, Rh, etc. can be used. Yes.

For example, Patent Document 1 discloses a method in which waste plastic and an FCC catalyst are charged into a reaction tank, gasified at a temperature of 350 to 500 ° C., and cooled to obtain an oil component. However, FCC catalysts composed of synthetic zeolite and the like are expensive, and thus there is a problem that the processing cost becomes high. For this reason, use of an inexpensive catalyst is required.
Patent Document 2 discloses a method of thermally decomposing a low molecular weight organic substance such as waste plastic by bringing it into contact with a specific mixed gas (a mixed gas obtained by reforming a steelworks byproduct gas) in a fluidized bed. It has been shown that converter dust generated in the steel making process is used as a catalyst (which is also a fluidized medium in a fluidized bed), and this converter dust is an inexpensive catalyst.

International Publication No. 2007/086348 JP 2014-37524 A

  The method shown in Patent Document 2 uses a mixed gas obtained by reforming a steelworks by-product gas as a reaction gas, and uses ironworks converter dust as a catalyst. It is possible to implement. However, in this method, the gasification rate (ratio of the amount of carbon contained in the produced gas out of the amount of input carbon) is not significantly improved as compared with the case where silica sand having no catalytic effect is used as a fluid medium. There was a problem. That is, it is estimated that the catalyst is not working effectively.

  Accordingly, an object of the present invention is to solve the above-described problems of the prior art and to fully exhibit the catalytic effect of the iron content contained in the converter dust, which is a catalyst for organic substance decomposition obtained from the converter dust. It is an object of the present invention to provide a catalyst for decomposing organic materials, a method for producing the same, and a method for reducing the molecular weight of organic materials.

  In order to solve the above-mentioned problems, the present inventors have conducted detailed studies on the reason why the catalytic effect cannot be sufficiently obtained when converter dust is used as a catalyst for decomposing organic substances, and countermeasures. As a result, the present inventors have a small catalytic effect of converter dust because iron oxide, which is effective as a catalyst, is covered with an outer shell layer (outermost layer) mainly composed of a calcium compound. It has been found that the catalytic effect of iron oxide contained in converter dust can be sufficiently exerted by removing the outer shell layer mainly composed of this calcium compound. Also, even if the outer shell layer mainly composed of the calcium compound remains, the outer shell layer is modified so that it can be easily peeled off when used as a catalyst for decomposing organic substances. It was also found that the desired catalytic effect can be obtained.

The present invention has been made on the basis of such knowledge and has the following gist.
[1] A method for producing a catalyst for decomposing organic substances from converter dust generated at a steelworks,
Prepare converter dust,
For decomposing organic substances, removing at least a part of the outer shell layer (a) mainly composed of calcium compounds from the converter dust and exposing the iron oxide layer (b) under the outer shell layer (a) A method for producing a catalyst.
[2] The method for producing an organic substance decomposition catalyst according to [1], wherein the converter dust is heat-treated in an oxidizing atmosphere to peel off at least a part of the outer shell layer (a).
[3] A method for producing a catalyst for decomposing organic substances from converter dust generated at a steel works,
Prepare converter dust,
A method for producing a catalyst for decomposing an organic substance, wherein the converter dust is heat-treated in an oxidizing atmosphere to reform at least a part of the outer shell layer (a) containing a calcium compound as a main component so as to be easily peeled off.
[4] The method for producing an organic substance decomposition catalyst according to the above [2] or [3], wherein the converter dust is heat-treated in a rotary kiln in an oxidizing atmosphere.
[5] A catalyst for decomposing an organic substance having an outer shell layer (a) and an iron oxide layer (b) in order from the surface,
The outer shell layer (a) is mainly composed of a calcium compound,
The iron oxide layer (b) is an organic substance decomposition catalyst in which at least a part is exposed.
[6] A catalyst for decomposing an organic substance having an outer shell layer (a) and an iron oxide layer (b) in order from the surface,
The outer shell layer (a) is mainly composed of a calcium compound,
The organic oxide decomposition catalyst, wherein the iron oxide layer (b) is modified so that at least a part thereof is easily peeled off.
[7] A method for reducing the molecular weight of an organic substance using the organic substance decomposition catalyst according to [5] or [6],
Prepare an organic substance and organic substance decomposition catalyst,
The organic substance is brought into contact with the reaction gas in the presence of the organic substance decomposition catalyst, and the organic substance is brought into contact with the reaction gas in the presence of the organic substance decomposition catalyst that is reduced in molecular weight by thermal decomposition. A method for reducing the molecular weight of organic substances that are reduced in molecular weight by decomposition.
[8] In the molecular weight reduction method according to [7], a fluidized bed including a fluidized medium containing the organic substance decomposition catalyst,
A method for reducing the molecular weight of an organic substance, wherein the organic substance is brought into contact with the reaction gas in the fluidized bed.

  The catalyst for decomposing an organic substance of the present invention is obtained by removing at least a part of the outer shell layer (a) mainly composed of a calcium compound covering the surface of the converter dust, and forming a lower layer of the outer shell layer (a). The iron oxide layer (b) can be effectively functioned as a catalyst because the iron oxide layer (b) is exposed or at least part of the outer shell layer (a) is easily detached during use as a catalyst. Thus, the catalytic effect of iron oxide contained in the converter dust can be sufficiently exhibited. For this reason, compared with the case where a conventional catalyst for decomposing organic substances made of unprocessed converter dust is used, the gasification rate of organic substances can be greatly improved, and a large amount of inexpensive and highly active catalysts can be obtained. It is possible to use and produce fuel from organic substances at low cost.

In FIG. 1, (A) is an SEM observation image of a cross section of untreated converter dust particles, and (B) is an SEM observation image of a cross section of converter dust particles from which a part of the outer shell layer has been removed by oxidation treatment. It is. FIG. 2 is an explanatory diagram showing an outline of the fluidized bed gasification test apparatus used in the examples.

In order to clarify the reason why the catalytic effect is small and the gasification rate is not sufficiently improved when the converter dust is used as a catalyst for decomposing organic substances, the inventors have embedded the converter dust in a resin, and SEM- Observed with EDX. In addition, components were also identified by wide-angle XDR analysis. As a result of these analyses, the particle structure of the converter dust has metallic iron at the center, and this metallic iron is covered with an iron oxide layer such as FeO and Fe ₃ O ₄ , and a calcium compound is mainly used as the outermost layer. It became clear that it was covered with the outer shell layer as a component. Converter dust is generated when the hot metal splashed during converter refining is made into droplets by surface tension, and flux (CaO (calcium oxide)) is mainly formed on the droplet surface during the generation. It is considered that the outer shell layer is formed as described above. In such converter dust, the iron oxide layer effective as a catalyst is covered with an outer shell layer mainly composed of a calcium compound, and the effective effective catalyst surface area is reduced, so that a sufficient catalytic effect is obtained. It was estimated that it was not possible.

  Therefore, the present inventors performed an oxidation treatment on the converter dust to remove the outer shell layer mainly composed of a calcium compound, and investigated the catalytic effect of the converter dust. As a result, it was found that by removing the outer shell layer, the effective catalyst surface area of the converter dust was greatly increased, and the gasification rate of the organic substance was improved when used as a catalyst.

FIGS. 1A and 1B show SEM observation images of cross-sections of untreated converter dust and converter dust particles from which a part of the outer shell layer has been removed by oxidation treatment. In addition, the component names identified by the wide-angle XDR analysis were displayed in each image. Converter dust is obtained by classifying the converter dust generated at an iron mill by air classification and removing a particle size of 40 μm or less. Fig. 1 (A) shows unprocessed converter dust, and Fig. 1 (B) shows that converter dust is put in a stainless steel bat and heat-treated (oxidation treatment) at 650 ° C for 30 minutes in an electric furnace in an air atmosphere. It is a thing. As shown in FIGS. 1A and 1B, the converter dust has metallic iron at the center, and this metallic iron is an iron oxide layer (in FIG. 1A, FeO + Fe ₃ O ₄ , FIG. 1B ) Is covered with Fe ₂ O ₃ + Fe ₃ O ₄ ), but the untreated converter dust in FIG. 1 (A) has an outer shell in which the entire iron oxide layer is mainly composed of a calcium compound (calcium hydroxide). Covered with layers. In contrast, the oxidized converter dust in FIG. 1 (B) has a part of the outer shell layer mainly composed of a calcium compound (calcium hydroxide is changed to calcium carbonate by the oxidation treatment). It is removed and the underlying iron oxide layer is exposed on the dust surface.

Converter dust is iron-containing dust that has been collected and collected by converter refining in the steelmaking process, and has a high component ratio of iron among the dust generated in steelworks, and is a catalyst for decomposing organic substances that is inexpensive and available in large quantities. (Including the case where it is used as a fluid medium having a catalytic function). Examples of the steelmaking process in which converter dust is generated include, but are not limited to, a dephosphorization process, a decarburization process, a stainless steel refining process, and the like.
The outer shell layer a of converter dust is mainly composed of a calcium compound derived from a flux (that is, containing 50% by mass or more of calcium compound), and includes a case of being composed only of a calcium compound. The calcium compound contained in the outer shell layer a is at least one of Ca (OH) ₂ , CaO, and CaCO ₃ . Components other than the calcium compound as the main component are derived from components other than Ca in the flux, hot metal, slag, and the like.

In the first manufacturing method according to the present invention, at least a part of the outer shell layer a mainly composed of the calcium compound of the converter dust is removed, and the iron oxide layer b under the removed outer shell layer a is removed as dust. It is exposed on the surface. Thereby, at least a part of the outer shell layer a mainly composed of the calcium compound of the converter dust is removed, and the organic oxide decomposition in which the iron oxide layer b below the removed outer shell layer a is exposed on the dust surface. The catalyst for use is obtained.
In the production method of the present invention, there is no particular limitation on the method for removing the outer shell layer a. For example, (a) the outer shell layer a is peeled off by heat treatment (oxidation treatment) of the converter dust in an oxidizing atmosphere. (B) a method in which the outer shell layer a is dissolved by treating the converter dust with an acid solution, and (c) a calcium compound (Ca (OH) constituting the outer shell layer a by heating the converter dust. ₂ ) A method of peeling the outer shell layer a by crushing mechanically after making the state easy to peel by desorbing the moisture in ₂ ) can be applied. Among these, the method (a) is preferable because it can be carried out easily and at low cost.

Here, the above “at least part” preferably has a removal rate of 20% by volume or more. That is, the outer shell layer a removed from the iron oxide layer b is 20% by volume or more (removal rate: 20%) with respect to the total amount (volume%) of the outer shell layer a formed on the iron oxide layer b before the removal. (Volume% or more) is preferable.
In the present invention, the above removal rate can be measured by image analysis of 10 or more particles from an SEM photograph observed at a magnification of 800 times.

In the method (a), at least a part of the outer shell layer a is peeled off by heat treating (oxidizing) the converter dust in an oxidizing atmosphere. (I) The outer shell layer a is formed by the heat treatment. The OH group of the calcium compound (Ca (OH) ₂ ) is eliminated and the outer shell layer a is cracked, and the outer shell layer a is easily peeled off. (Ii) Heat treatment in an oxidizing atmosphere (oxidation treatment) ), Fe ₃ O ₄ in the converter dust is oxidized to Fe ₂ O ₃ and the crystal structure changes from cubic to hexagonal and shrinks, so the iron oxide layer b shrinks relative to the outer shell layer a. It can be considered that the interface between the iron oxide layer b and the outer shell layer a is peeled off.
The converter dust from which a part of the outer shell layer a is peeled and removed by such an action is used in the process of being used as a catalyst for decomposing organic matter even if the outer shell layer a that does not peel remains. a further peels and contributes to the improvement of the catalytic effect. In particular, when used in a fluidized bed, peeling of the outer shell layer a is promoted by contact with other particles.

The oxidizing atmosphere for heat treating the converter dust may be an atmosphere (gas composition, temperature condition) that can oxidize FeO to Fe ₃ O ₄ or Fe ₂ O ₃ . Although CO ₂ can be used as a gas for promoting oxidation, an air atmosphere is desirable in order to perform the treatment at a low cost. The heat treatment temperature (heating temperature) is preferably 600 to 900 ° C. When the heat treatment temperature is less than 600 ° C., the oxidation rate is slow. On the other hand, when the heat treatment temperature exceeds 900 ° C., the iron oxide exposed by the peeling of the outer shell layer a may be sintered with dust and firmly fixed. Furthermore, considering the heat transfer time to the converter dust and the time required for the oxidation of Fe ₃ O ₄ , the heat treatment time is preferably 15 minutes or more.
As a heat treatment method, batch-type heat treatment using an electric furnace is possible, but in the case of continuous treatment as an industrial process, it is preferable to use a rotary kiln.

  Thus, in the present invention, the outer shell layer a and the iron oxide layer b are formed in order from the surface by the first manufacturing method, and the outer shell layer a is mainly composed of the calcium compound, and the iron oxide layer b. It is possible to obtain a catalyst for decomposing organic substances in which at least a part of the catalyst is exposed.

On the other hand, the converter dust can be modified so that at least a part of the outer shell layer a is easily peeled even if the outer shell layer a mainly composed of the calcium compound still exists. . Thereby, when used as a catalyst for decomposing organic substances, the outer shell layer a easily peels off, and a desired catalytic effect is obtained. For this reason, in the second manufacturing method according to the present invention, the converter dust is heat-treated in an oxidizing atmosphere (oxidation treatment) to modify at least a part of the outer shell layer a so as to be easily peeled off. . As a result, a catalyst for decomposing an organic substance, which has been modified so that at least a part of the outer shell layer a containing a calcium compound as a main component is easily peeled, is obtained.
Here, the above “easy to peel” refers to a state where the outer shell layer a covers the iron oxide layer b while the outer shell layer a is cracked.

Moreover, it is preferable that said "at least one part" in a 2nd manufacturing method is also 20 volume% or more as a removal rate. That is, the outer shell layer a removed from the iron oxide layer b is 20% by volume or more (removal rate: 20%) with respect to the total amount (volume%) of the outer shell layer a formed on the iron oxide layer b before the removal. (Volume% or more) is preferable.
Similarly, the removal rate can be measured by image analysis of 10 or more particles from an SEM photograph observed at a magnification of 800 times after the outer shell layer a peels from the iron oxide layer b.

When the converter dust is heat-treated in an oxidizing atmosphere (oxidation treatment), at least a part of the outer shell layer a is easily peeled off. This is considered to be due to almost the same action. That is, (i) the state in which the outer shell layer a is easily peeled off due to the OH group of the calcium compound (Ca (OH) ₂ ) constituting the outer shell layer a being removed by heat treatment and the outer shell layer a being cracked. (Ii) By heat treatment in an oxidizing atmosphere, Fe ₃ O ₄ in the converter dust is oxidized to Fe ₂ O ₃ and the crystal structure changes from cubic to hexagonal and shrinks, so that the outer shell layer This is considered to be due to the action that the iron oxide layer b contracts with respect to a and the interface between the iron oxide layer b and the outer shell layer a becomes more easily peeled.
The conditions for this oxidation treatment are the same as the oxidation treatment in the first manufacturing method described above. Preferably, the heat treatment temperature (heating temperature) is 600 to 900 ° C., and the heat treatment time is 5 minutes or more and 10 minutes or less.

The organic substance decomposition catalyst obtained in the present invention is used for reducing the molecular weight (gasification / oilification) by thermal decomposition by bringing an organic substance into contact with a reaction gas.
That is, in the method for reducing the molecular weight of an organic substance according to the present invention, the organic substance is brought into contact with a reaction gas in the presence of the organic substance decomposition catalyst to reduce the molecular weight by pyrolysis (gasification or oilification). To do.
There are no particular restrictions on the organic substance (solid) that is subject to thermal decomposition, but high molecular weight organic substances are suitable, for example, resins (usually resin waste such as waste plastics), biomass, etc. One or more of these can be targeted.
Examples of the resins include polyolefins such as PE and PP, thermoplastic polyesters such as PA and PET, elastomers such as PS, thermosetting resins, synthetic rubbers and foamed polystyrene. It is not limited to.
Examples of biomass include, but are not limited to, sewage sludge, paper, wood (for example, construction waste wood, packaging / transport waste wood, thinned wood, etc.).

There are no particular restrictions on the type of reaction vessel in which an organic substance and a reaction gas are brought into contact with each other in the presence of an organic substance decomposition catalyst. For example, a horizontal moving bed reactor (such as a rotary kiln) or a vertical reactor filled with a catalyst. A fluidized bed reactor can be used, and among these, a fluidized bed reactor is particularly preferable from the viewpoint of processing efficiency.
When using a fluidized bed reactor, the organic substance decomposition catalyst obtained in the present invention is used as at least a part of the fluidized medium, the organic substance is brought into contact with the reaction gas in the fluidized bed of the fluidized medium, and the organic substance is heated. Decompose to lower molecular weight (gasification or oil conversion).

Further, the type of reaction gas to be brought into contact with the organic substance is not particularly limited, and is not limited to a known gasifying agent, for example, a mixed gas shown in Patent Document 2 (exhaust gas containing carbon monoxide generated in a metallurgical furnace). By performing the shift reaction by adding water vapor, a mixed gas including hydrogen and carbon dioxide gas generated by the shift reaction and water vapor not consumed in the shift reaction can be used.
Gases and oils generated by reducing the molecular weight by thermal decomposition of organic substances can be effectively used as gaseous fuels and liquid fuels.

The converter dust generated at the steelworks is classified by wind, and the particle size of 40 μm or less is removed and placed in a stainless steel bat, and oxidized in the air furnace in the air atmosphere under the conditions shown in Table 1 and shown in FIG. 1 (B). The catalyst for organic substance decomposition | disassembly consisting of the converter dust from which a part of outer shell layer a to show and the lower iron oxide layer b exposed was exposed was obtained.
In the fluidized bed gasification test apparatus shown in FIG. 2, waste plastic gasification tests (Examples 1 and 2 of the present invention) were carried out using the organic substance decomposition catalyst as a fluidized medium. In addition, using the same apparatus, gasification test using silica sand as a fluid medium (Comparative Example 1), untreated converter dust (converter dust generated at a steel mill is air-classified, particle size of 40 μm or less A gasification test (Comparative Example 2) was carried out using a catalyst for decomposing organic substances consisting of a fluid medium as a fluid medium.

In the fluidized bed gasification test apparatus shown in FIG. 2, 1 is a fluidized bed type pyrolysis furnace, and 2 is a fluidized bed. The pyrolysis furnace 1 is formed above a fluidized bed 2 formed of a fluidized medium, a windbox portion 5 into which fluidized gas is introduced from a gas supply pipe 3, and a windbox portion 5, And a dispersion plate 4 that blows upward. In this pyrolysis furnace 1, a flowing gas (gasification agent) is introduced into the wind box portion 5 below the dispersion plate 4 through the gas supply pipe 3, and the flowing gas is blown out of the dispersion plate 4, whereby the dispersion plate 4. A fluidized bed 2 made of a fluidized medium is formed above the substrate. The organic substance put into the pyrolysis furnace 1 is pyrolyzed in the fluidized bed 2 to become a gas product. The gas containing the gaseous product is discharged through the discharge pipe 6. The organic substance put in the hopper 7 is cut out by the table feeder 8 and falls from the upper part of the pyrolysis furnace 1 to the fluidized bed 2. The flowing gas (gasification agent) supplies water from the tank 9 to the steam generator 10 by the pump 11 to generate steam, and N ₂ , H ₂ and CO ₂ are added to the steam from the gas cylinders 12, 13 and 14. As a result, steam is prepared, and this flowing gas (mixed gas of H ₂ O, N ₂ , H ₂ , CO ₂ ) is introduced into the pyrolysis furnace 1 through the gas supply pipe 3. After the gas in the pyrolysis furnace 1 discharged from the discharge pipe 6 is cooled by the gas cooler 15 (18 is a gas trap), the gas flow rate is continuously measured by the mass flow meter 16, and further the gas chromatography. At 17 the gas composition is measured.

1800 g of the fluid medium (fluid medium / catalyst in the present invention and Comparative Example 2) was used. The diameter of the fluidized bed 2 (fluidized bed gasification furnace) was 66 mm, and the height of the fluidized medium at rest was 198 mm. As a flowing gas (gasifying agent), a mixed gas of H ₂ , N ₂ , CO ₂ , and H ₂ O was supplied at 4 L / min. As the organic substance, waste plastic particles molded to about 6 mmφ × 15 mm by a ring die molding machine were frozen and pulverized to a particle size of about 1 mm. Waste plastic particles placed in the hopper 7 were cut out by the table feeder 8 at a cutting speed of 300 g / h, and dropped into the fluidized bed 2 from the top of the pyrolysis furnace 1.

In the present invention example and the comparative example, the lower gas calorific value and gasification rate were determined from the gas generation amount and gas composition. The results are shown in Table 1 together with the converter dust oxidation conditions.
The gasification rate is obtained by the following equation, and the “gasification raw material” is waste plastic particles.
F = {(G × C2-V × C3) / (M × C1)} × 100
Where F: Gasification rate (%)
M: Gasification raw material supply amount (kg / h)
V: Gasification agent supply amount (kg / h)
G: Amount of generated gas (kg / h)
C1: Carbon concentration in gasification raw material (%)
C2: Carbon concentration in product gas (%)
C3: Carbon concentration in gasifying agent (%)

According to Table 1, compared with Comparative Example 1 using silica sand as a fluid medium, in Comparative Example 2 using untreated converter dust, although the generated gas heat generation amount increases, the gasification rate hardly changes. On the other hand, in the present invention examples 1 and 2 using the converter dust from which a part of the outer shell layer a is removed, the heat generation amount of the generated gas is increased, but the gasification rate is greatly improved.

DESCRIPTION OF SYMBOLS 1 Pyrolysis furnace 2 Fluidized bed 3 Gas supply pipe 4 Dispersion plate 5 Air box part 6 Discharge pipe 7 Hopper 8 Table feeder 9 Tank 10 Steam generator 11 Pump 12-14 Gas cylinder 15 Gas cooler 16 Mass flow meter 17 Gas chromatography 18 Gas trap

Claims (8)

A method for producing a catalyst for decomposing organic substances from converter dust generated at a steel mill,
Prepare converter dust,
For decomposing organic substances, removing at least a part of the outer shell layer (a) mainly composed of calcium compounds from the converter dust and exposing the iron oxide layer (b) under the outer shell layer (a) A method for producing a catalyst.   The manufacturing method of the catalyst for organic substance decomposition | disassembly of Claim 1 which heat-processes the said converter dust in oxidizing atmosphere, and peels at least one part of the said outer shell layer (a). A method for producing a catalyst for decomposing organic substances from converter dust generated at a steel mill,
Prepare converter dust,
A method for producing a catalyst for decomposing an organic substance, wherein the converter dust is heat-treated in an oxidizing atmosphere to reform at least a part of the outer shell layer (a) containing a calcium compound as a main component so as to be easily peeled off.   The manufacturing method of the catalyst for organic substance decomposition | disassembly of Claim 2 or Claim 3 which heat-processes the said converter dust in the rotary kiln of oxidizing atmosphere. In order from the surface, an organic substance decomposition catalyst having an outer shell layer (a) and an iron oxide layer (b),
The outer shell layer (a) is mainly composed of a calcium compound,
The iron oxide layer (b) is an organic substance decomposition catalyst in which at least a part is exposed. In order from the surface, an organic substance decomposition catalyst having an outer shell layer (a) and an iron oxide layer (b),
The outer shell layer (a) is mainly composed of a calcium compound,
The organic oxide decomposition catalyst, wherein the iron oxide layer (b) is modified so that at least a part thereof is easily peeled off. A method for reducing the molecular weight of an organic substance using the organic substance decomposition catalyst according to claim 5,
Prepare an organic substance and organic substance decomposition catalyst,
A method for reducing the molecular weight of an organic substance, wherein the organic substance is brought into contact with a reaction gas in the presence of the catalyst for decomposing the organic substance, and the molecular weight is reduced by thermal decomposition. Preparing a fluidized bed containing a catalyst for decomposing the organic substance in a fluidized medium;
The method for reducing the molecular weight of an organic substance according to claim 7, wherein the organic substance is brought into contact with the reaction gas in the fluidized bed.