Spontaneous heat generation inhibitor for carbon resources, method for inhibiting spontaneous heat generation for carbon resources, and method for storing carbon resources

Abstract

The present invention provides a spontaneous heat generation inhibitor for carbon resources, characterized by containing naphthenic ring carbon atoms at a ratio of 1 mmol / g or more. Also provided is a method for suppressing spontaneous heat generation for carbon resources, characterized by adding a spontaneous heat generation inhibitor for carbon resources, characterized by containing naphthenic ring carbon atoms at a ratio of 1 mmol / g or more, to a carbon resource in an amount of 1 mass % or more, and a method for storing carbon resources, characterized by storing a mixture obtained by the method for suppressing spontaneous heat generation for carbon resources.

Description

[Technical Field]

[0001] The present disclosure relates to a spontaneous heat generation inhibitor for carbon resources, a method for suppressing spontaneous heat generation for carbon resources, and a method for storing carbon resources. This application claims priority based on Japanese Patent Application No. 2024-040976, filed on March 15, 2024, the contents of which are incorporated herein by reference. [Background technology]

[0002] For example, the steel industry uses large amounts of carbon resources. Here, carbon resources are resources containing carbon atoms. Carbon resources are, for example, those that obtain heat by burning carbon atoms or those that are used as reducing agents. Carbon resources include, for example, petroleum, coal, and biomass carbonaceous materials. Biomass carbonaceous materials are carbonaceous materials obtained by dry distilling biomass.

[0003] Depending on the type of carbon resource, spontaneous heating of the carbon resource may become a problem. For example, coal and woody biomass charcoal are prone to spontaneous heating. Therefore, when storing large quantities of these materials, careful temperature control is required.

[0004] Patent Documents 1 to 3 disclose techniques for suppressing spontaneous heating of carbon resources. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2001-164254 [Patent Document 2] Japanese Patent Application Publication No. 2011-201947 [Patent Document 3] Japanese Patent Publication No. 59-074189 Summary of the Invention [Problem to be solved by the invention]

[0006] The present inventors considered that the techniques disclosed in Patent Documents 1 to 3 cannot sufficiently suppress spontaneous heating of carbon resources. The present disclosure has been made in consideration of the above problems, and an object of the present disclosure is to provide a spontaneous heat generation inhibitor for carbon resources that can more reliably suppress spontaneous heat generation of carbon resources. [Means for solving the problem]

[0007] The gist of this disclosure is as follows. (1) A spontaneous heat generation inhibitor for carbon resources, characterized by containing naphthenic ring carbon atoms in a ratio of 1 mmol / g or more. (2) The spontaneous heat generation inhibitor for carbon resources according to (1), characterized in that it contains naphthenic ring carbon atoms in a proportion of 5 mmol / g or more. (3) The spontaneous heat generation inhibitor for carbon resources according to (1) or (3), characterized in that the naphthenic ring having the naphthenic ring carbon atom has an unsaturated carbon bond. (4) The spontaneous heat generation inhibitor for carbon resources according to (3), wherein the unsaturated carbon bond is an aromatic carbon bond. (5) The spontaneous heat generation inhibitor for carbon resources according to (1) or (2), characterized in that it has a condensed ring structure in its molecular structure, and a naphthenic ring carbon atom is contained in the condensed ring structure. (6) The spontaneous heat generation inhibitor for carbon resources according to any one of (1) to (5), which is composed of a mixture having a molecular weight of 200 to 1,000. (7) The spontaneous heat generation inhibitor for carbon resources according to any one of (1) to (6), which is solid at room temperature. (8 ) (1)~( 7 1. A method for suppressing spontaneous heat generation of a carbon resource, comprising the step of adding 1% by mass or more of the spontaneous heat generation inhibitor for a carbon resource according to any one of claims 1 to 1. ( 9) ( 8 10. A method for storing carbon resources, comprising storing a mixture obtained by the method for suppressing spontaneous heat generation of carbon resources described in (1). [Effects of the Invention]

[0008] According to the present disclosure, it is possible to provide a spontaneous heat generation inhibitor for carbon resources that can more reliably suppress spontaneous heat generation of carbon resources. Furthermore, according to the present disclosure, it is possible to provide a method for suppressing spontaneous heat generation of carbon resources and a method for storing carbon resources that can more reliably suppress spontaneous heat generation of carbon resources. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a graph showing the relationship between the elapsed time from the start of a spontaneous heating evaluation test and the sample temperature. DETAILED DESCRIPTION OF THE INVENTION

[0010] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the present disclosure is not limited to the examples described below. While specific numerical values ​​and materials may be used in the following description, other numerical values ​​and materials may be used as long as the effects of the present disclosure are achieved. Furthermore, the components of the following embodiments can be combined with each other. Furthermore, in this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. In this specification, the term "process" includes not only an independent process, but also a process that cannot be clearly distinguished from other processes as long as the intended purpose of the process is achieved.

[0011] <1. Findings of the Inventor> It has been suggested that free radicals generated in the carbonaceous materials are involved in the spontaneous heating of carbonaceous resources. Furthermore, naphthenic carbon has hydrogen-donating properties, and its chemical properties are considered important in coal liquefaction reactions, for example, as it donates hydrogen to the thermal decomposition radicals of coal, stabilizing the low-molecular-weight compounds derived from coal. Spontaneous heating refers to heat generation in an oxygen atmosphere, and also refers to heat generation in air at normal pressure.

[0012] Here, the naphthenic ring means a ring having a 4- to 6-membered ring structure of carbon atoms, and a carbon atom bonded to two hydrogen atoms (naphthenic ring carbon atom) is included in the ring structure. The cyclic structure constituting the naphthenic ring may be a single cyclic structure or a plurality of condensed cyclic structures.

[0013] An example of the chemical structure of a naphthenic ring is shown below: In the example below, the carbon atoms in the positions enclosed by the dotted circle are the naphthenic ring carbon atoms.

[0014] [ka]

[0015] Among the above examples, the naphthenic rings of (a), (c), and (d) have an unsaturated bond in the ring structure. The naphthenic ring of (b) has a ring structure with a saturated bond. The naphthenic ring of (d) is a condensed ring of two ring structures. Note that the above example shows only a portion of the molecular structure, and the compound constituting the spontaneous heat generation inhibitor according to this embodiment does not necessarily have such a compound. That is, the naphthenic ring as described above may be included as part of the structure of the compound described below. For example, any of the carbon atoms constituting the naphthenic ring may be bonded to a carbon atom or another functional group to form the compound.

[0016] Naphthenic ring carbon atoms easily release hydrogen atoms. In other words, naphthenic ring carbon atoms have hydrogen donating properties. Therefore, the present inventors believed that the hydrogen atoms released from the naphthenic ring carbon atoms would capture free radicals that could induce spontaneous heating of the carbon resource, thereby suppressing spontaneous heating of the carbon resource. However, no quantitative study has been conducted to date on the necessary proportion of naphthenic ring carbon atoms to suppress spontaneous heating of the carbon resource.

[0017] An example of a substance that contains naphthenic ring carbon atoms and is relatively inexpensive and easily available is petroleum pitch. However, since it is the naphthenic ring carbon atoms that suppress the spontaneous heat generation of carbon resources, any substance that contains a large number of naphthenic ring carbon atoms should function as a spontaneous heat generation suppressor for carbon resources, regardless of its origin. This embodiment has been made based on the above findings.

[0018] <2. Spontaneous heat suppressant for carbon resources> The spontaneous heating inhibitor for carbon resources according to this embodiment (hereinafter also referred to simply as "spontaneous heating inhibitor") is a substance having a molecular structure containing naphthenic rings, and contains naphthenic ring carbon atoms at a ratio of 1 mmol / g or more. As described above, naphthenic ring carbon atoms have hydrogen-donating properties. Therefore, hydrogen atoms released from the naphthenic ring carbon atoms capture free radicals that could induce spontaneous heating of the carbon resource, thereby suppressing spontaneous heating of the carbon resource. However, as shown in the examples described below, such an effect can be obtained when the spontaneous heating inhibitor contains at least 1 mmol / g of naphthenic ring carbon atoms.

[0019] The spontaneous heating inhibitor according to this embodiment may preferably contain naphthenic ring carbon atoms at a ratio of 5 mmol / g or more. The upper limit of the content of naphthenic ring carbon atoms is not particularly limited, but may be 30 mmol / g or less, 25 mmol / g or less, or 15 mmol / g or less.

[0020] The content of naphthenic ring carbon atoms may be calculated based on the molecular structure of the spontaneous heat generation inhibitor and the number of naphthenic ring carbon atoms contained in one molecule. Specifically, the molecular weight is determined from the molecular structure, and the content of naphthenic ring carbon atoms can be calculated based on the molecular weight and the number of naphthenic ring carbon atoms contained in one molecule.

[0021] If the molecular structure of a candidate spontaneous heat suppressant is unknown, the average molecular structure can be determined using the following procedure. The average molecular structure does not necessarily match the actual molecular structure of the candidate spontaneous heat suppressant, but it reflects the molecular structure characteristics (type and number of functional groups, etc.) of the candidate spontaneous heat suppressant.

[0022] Specifically, the content (mass %) of each element is determined, and the average molecular structure is determined. The content of each element is determined by performing elemental analysis of the spontaneous heat generation inhibitor using a method in accordance with JIS M 8813:2006.

[0023] The average molecular structure is 1 H NMR measurement and 13 Determined by C NMR measurement. 1 The results of H NMR measurement reveal the proportions of four types of H: Ha, Hα, Hβ, and Hγ. The proportion of H refers to the proportion of Ha, Hα, Hβ, or Hγ relative to the total amount of H contained in the spontaneous heat generation inhibitor. The four types of H are: 1 In the H NMR spectrum, these H can be distinguished because they exhibit chemical shift values ​​in the ranges of Ha: 9.0-6.0 ppm, Hα: 5.0-2.0 ppm, Hβ: 2.0-1.05 ppm, and Hγ: 1.05-0.5 ppm.

[0024] Also, 13 The results of C NMR measurements reveal the number of aromatic carbon atoms and the number of oxygen-containing groups such as aldehyde groups, ketone groups, and carboxyl groups.

[0025] Based on these NMR measurement results, the average molecular structure is constructed. The specific method for constructing the average molecular structure is carried out in accordance with the method described in Yuki Hata, et al., ISIJ International, Vol. 62 (2022), No. 5, pp. 948-95.

[0026] The specific conditions for NMR measurement are as follows: The solvent used is a heavy solvent such as deuterated chloroform. 1 1 H NMR spectra are measured using the Single Pulse method. 13 C NMR spectra are measured using the single pulse method, and NOE (nuclear Overhauser effect) is not used.

[0027] As described above, based on the average molecular structure determined by NMR measurement, the molecular weight is further determined by mass spectrometry or GPC (Gel Permeation Chromatography).Then, based on the obtained molecular weight and the number of naphthenic ring carbon atoms contained in the average molecular structure, the content of naphthenic ring carbon atoms is calculated.

[0028] The spontaneous heat generation inhibitor according to this embodiment is a compound or a mixture. More preferably, the spontaneous heat generation inhibitor is a mixture. The mixture is composed of two or more different compounds. The average molecular structure of such a mixture can be determined by the above-described method, and the content of naphthenic ring carbon atoms contained in the average molecular structure can be calculated.

[0029] When the spontaneous heat generation inhibitor is a mixture and the molecular structure of each compound contained in the mixture is desired, the content of naphthenic ring carbon atoms contained in the mixture is calculated by adding up the naphthenic ring carbon atoms contained in each compound. When the spontaneous heat generation inhibitor is a single compound, the content of naphthenic ring carbon atoms contained in the molecular structure of that compound may be calculated.

[0030] When spontaneous heat generation inhibitors are made from natural resources, they are often composed of a mixture of multiple compounds due to the raw materials and processing steps. When the spontaneous heat generation inhibitor is a mixture of multiple compounds, the mixture may contain tens of thousands of compounds, making it difficult to identify the compounds, but it is known that the molecular weight of the mixture is distributed in the range of 200 to 10,000. The spontaneous heat generation inhibitor of this embodiment is made of a mixture with a molecular weight of 200 to 1000, thereby achieving a higher suppression effect.

[0031] The spontaneous heat generation inhibitor consisting of a mixture with a molecular weight of 200 to 1000 means that the peak of the molecular weight measured using an FD-MS device is in the range of 200 to 1000.

[0032] Specifically, the molecular weight peak is measured as follows. The molecular weight was measured using the FD-MS method, and the molecular weight peak was measured. Specifically, 1 mg of sample was dissolved in tetrahydrofuran and applied to an emitter (a tungsten wire with a diameter of approximately 10 μm and carbon whiskers attached to the surface). The current applied to the emitter was adjusted under high vacuum, and the sample molecules were directly ionized in combination with a high electric field, and a mass spectrum was obtained using a mass spectrometer. The detector voltage was set to 2200 V, the measurement mass range was 50 to 1600 m / z, and drift correction was performed using C. 20 H 16 This is done with the mass number (252.09396).

[0033] Furthermore, the spontaneous heat generation inhibitor according to this embodiment may have a fused ring structure within its molecular structure, and this fused ring structure may have a naphthenic ring carbon atom. The naphthenic ring carbon atom contained in the fused ring structure may have high hydrogen donating property.

[0034] Examples of fused ring structures contained in the compounds that constitute the spontaneous heat generation inhibitor according to this embodiment are shown below. Note that the structures exemplified below only show part of the molecular structure, and the compounds that constitute the spontaneous heat generation inhibitor do not necessarily have the structures shown below. In other words, the compounds according to this embodiment contain fused ring structures such as those shown below as part of their structures.

[0035] [ka]

[0036] Any of the carbon atoms constituting the above fused ring structure may be bonded to a carbon atom or another functional group to form a compound.

[0037] For example, the compound constituting the spontaneous heat generation inhibitor according to this embodiment may be an alicyclic compound having a cyclic aliphatic structure.

[0038] Furthermore, the spontaneous heat generation inhibitor according to this embodiment may have a structure in which the naphthenic rings (a) to (d) described above are condensed.

[0039] The carbon resource according to this embodiment may be solid at room temperature. This is because compounds having a naphthenic ring often have sublimation properties and therefore react efficiently with the carbon resource even in a solid state. Furthermore, the spontaneous heat generation inhibitor according to this embodiment is solid but has viscosity, and therefore has high adhesion to the carbon resource in a solid state and high reaction efficiency.

[0040] The spontaneous heat generation inhibitor according to this embodiment more preferably has an unsaturated carbon bond in a naphthenic ring having a naphthenic ring carbon atom. By having an unsaturated carbon bond in the naphthenic ring, the hydrogen donating ability is enhanced.

[0041] In the spontaneous heat generation inhibitor according to this embodiment, it is more preferable that the unsaturated carbon bond of the naphthenic ring having the naphthenic ring carbon atom has aromaticity. That is, it is more preferable that the unsaturated carbon bond is an aromatic carbon bond. This has the effect of improving the hydrogen donating performance and stabilizing the radicals generated during oxidation.

[0042] <3. Method for producing spontaneous heat suppressant from carbon resources> Next, a method for producing the spontaneous heat generation inhibitor for carbon resources will be described. The present inventors have found that the spontaneous heat generation inhibitor for carbon resources is a component contained in the carbon resource or a carbon resource dry distillation product. Therefore, the spontaneous heat generation inhibitor for carbon resources according to this embodiment can be extracted from the carbon resource or a carbon resource dry distillation product by solvent fractionation. Here, the explanation will be given on the premise that there are two carbon resources: a carbon resource as a raw material for the carbon resource spontaneous heat generation inhibitor, and a carbon resource whose spontaneous heat generation should be suppressed; however, these two carbon resources may be the same carbon resource or may be different.

[0043] First, a raw material is prepared. Here, the raw material is a carbon resource or a carbon distillation product of the carbon resource. A carbon resource is a resource containing carbon atoms, and heat is obtained by burning the carbon atoms. Examples of carbon resources are petroleum, coal, and woody biomass carbonaceous material. Woody biomass carbonaceous material is biomass made from wood. Examples of carbon distillation products of carbon resources are petroleum pitch, carbonaceous material obtained by dry distilling coal or woody biomass carbonaceous material, more specifically, coal tar, etc.

[0044] Next, the carbon resource or the carbon resource dry distillation product is extracted with hexane (first step). Specifically, for example, the carbon resource or the carbon resource dry distillation product and hexane are thoroughly mixed and allowed to stand. Next, the liquid portion is recovered, and the hexane is removed from the liquid portion. This yields a spontaneous heat generation inhibitor for the first carbon resource. As shown in the examples, the spontaneous heat generation inhibitor for the first carbon resource has a sufficient spontaneous heat generation inhibitory effect.

[0045] More specifically, the first step is carried out in the following manner. 1. Place 2 g of the first carbon source in a centrifuge tube. Add 50cc of hexane to the centrifuge tube in 2.1 and apply ultrasonic vibration for 10 minutes. The centrifuge tube from 3.2 is centrifuged to separate the solid from the liquid. The supernatant obtained in step 4.3 is collected and filtered to obtain the extract (hexane-soluble components). Repeat steps 2 to 4 twice on the extraction residue in the centrifuge tube after step 5.4 (for a total of three times). 6. The extract obtained in steps 1 to 5 above is evaporated to remove the solvent (hexane). The extract (hexane-soluble components) and extraction residue (hexane-insoluble components) recovered in step 7.6, and the extraction residue (hexane-insoluble components) on the filter paper recovered in steps 1 to 5 are placed in a vacuum dryer and left to stand at 80°C for 12 hours to remove the solvent contained in the extraction residue, thereby obtaining the hexane-soluble components and hexane-insoluble components.

[0046] The method for producing a spontaneous heat generation inhibitor for a carbon resource may be terminated when the spontaneous heat generation inhibitor for the first carbon resource is obtained, or the following second step may be further carried out. That is, the insoluble residue from the first step is extracted with toluene (second step). For example, the insoluble residue from the first step is thoroughly mixed with toluene and allowed to stand. Next, the liquid portion is recovered, and the toluene is removed from the liquid portion. In this way, a spontaneous heat generation inhibitor for a second carbon resource is obtained. As shown in the examples, the spontaneous heat generation inhibitor for the second carbon resource has a sufficient spontaneous heat generation inhibitory effect.

[0047] More specifically, the second step is carried out in the following manner. 8. Repeat steps 1 to 7 multiple times to obtain 2 g or more of the hexane-insoluble component, and collect 2 g of the hexane-insoluble component and place it in a centrifuge tube. Add 50 cc of toluene to the centrifuge tube in 9.8 and apply ultrasonic vibration for 10 minutes. 10.9 The centrifuge tube is placed in a centrifuge to separate the solid and liquid. 11. The supernatant obtained in step 10 is collected and filtered to obtain the extract (toluene-soluble components). 12.11 After step 12.11, for the extraction residue in the centrifuge tube, change the solvent from 50cc of hexane to 50cc of toluene and repeat steps 2 to 4 twice (for a total of three times). 13. The extract obtained in steps 12 above is evaporated to remove the solvent (toluene). The extract (toluene-soluble components) and extraction residue (toluene-insoluble components) recovered in steps 14.13 and the extraction residue (toluene-insoluble components) on the filter paper recovered in steps 11 through 12 are placed in a vacuum dryer and left to stand at 80°C for 12 hours to remove the solvent contained in the extraction residue, yielding the hexane-insoluble / toluene-soluble components and toluene-insoluble components.

[0048] Furthermore, spontaneous heat generation inhibitors for the second carbon resource often contain more naphthenic ring carbon atoms than spontaneous heat generation inhibitors for the first carbon resource. Therefore, spontaneous heat generation inhibitors for the second carbon resource can more reliably suppress spontaneous heat generation of the carbon resource than spontaneous heat generation inhibitors for the first carbon resource. Because this production method is a simple method involving solvent fractionation of the carbon resource or the carbon resource dry distillation product, spontaneous heat generation inhibitors for carbon resources can be produced at low cost and do not generate CO2 gas during production.

[0049] The spontaneous heat generation inhibitor according to this embodiment only needs to contain naphthenic ring carbon atoms in a proportion of 1 mmol / g or more, and therefore a substance having such a molecular structure may be directly produced by organic synthesis. The substance obtained in this manner also serves as the spontaneous heat generation inhibitor according to this embodiment.

[0050] The components contained in the carbon resource dry distillation products are substances listed on pages 479 to 526 of the Aromatic and Tar Industry Handbook, Third Edition (Japan Aromatic Industry Association).

[0051] <4. Methods for suppressing spontaneous heat generation of carbon resources> In the method for suppressing spontaneous heat generation of a carbon resource according to this embodiment, the spontaneous heat generation inhibitor for a carbon resource according to this embodiment is added in an amount of 1 mass % or more relative to the carbon resource. As shown in the examples, a sufficient spontaneous heat generation suppression effect can be obtained by setting the mass ratio to 1 mass % or more. For the purpose of achieving homogeneous kneading, the spontaneous heat generation inhibitor is preferably added in an amount of 3% by mass or more, and even more preferably 5% by mass or more, relative to the carbon resource. There is no particular upper limit to the mass ratio, but it may be, for example, 30% by mass.

[0052] <5. Carbon resource storage methods> In the method for storing a carbon resource according to this embodiment, the mixture obtained by the method for suppressing spontaneous heat generation of a carbon resource is stored. The atmosphere during storage is not particularly limited, and the mixture may be stored in the air.

[0053] <6. Use as a spontaneous heat suppressant> The present disclosure also includes use of a spontaneous heat generation inhibitor of a carbon resource characterized by containing naphthenic ring carbon atoms in a proportion of 1 mmol / g or more. The present disclosure also includes use of a spontaneous heat buildup inhibitor of a carbon resource characterized by containing naphthenic ring carbon atoms in a proportion of 5 mmol / g or more. This carbon resource spontaneous heat inhibitor may have the features of the above-described embodiments. [Example]

[0054] Example 1 Next, an example of this embodiment will be described. In this example, acacia-derived woody biomass charcoal was prepared as a carbon resource whose spontaneous heat generation is to be suppressed. Acacia-derived woody biomass charcoal has a high spontaneous heat generation property.

[0055] Meanwhile, a spontaneous heat generation inhibitor for carbon resources was prepared using the following steps. First, petroleum-based pitch (ASP) was prepared. Here, commercially available petroleum-based pitch was used. Next, 2 g of petroleum-based pitch was extracted with 50 cc of hexane (first step) using the procedure described in the above embodiment. The extraction was performed at a temperature of 25°C and atmospheric pressure. After that, the hexane was evaporated to obtain a residue, an additive (HS). HS corresponds to the spontaneous heat generation inhibitor for carbon resources in the above embodiment.

[0056] Next, 2 g of the insoluble residue from the first step was extracted with 50 cc of toluene. The extraction was performed at a temperature of 25°C and atmospheric pressure. This resulted in the production of an additive (HI-TS). The insoluble residue insoluble in hexane and toluene was designated as an additive (TI). HI-TS corresponds to the spontaneous heating inhibitor for the second carbon resource in the above embodiment. TI is the insoluble residue of the ASP that is insoluble in toluene.

[0057] Next, the average molecular structures of HS, HI-TS, and TI were determined by the method described above. That is, elemental analysis of HS, HI-TS, and TI was performed according to a method in accordance with JIS M 8813 or JIS M 8819, and the mass% of each element was determined. 1 H NMR measurement and 13 C NMR measurements were carried out (solvent: deuterated chloroform). Based on these results, the average molecular structure was constructed. The specific construction of the average molecular structure was carried out according to Yuki Hata, et al., ISIJ International, Vol. 62 (2022), No. 5, pp. 948-95. The molecular weight was calculated from the average molecular structure thus obtained, and the content of naphthenic ring carbon atoms was calculated based on the molecular weight and the number of naphthenic ring carbon atoms contained in the average molecular structure.

[0058] The results are shown in Table 1. HS and HI-TS contain naphthenic ring carbon atoms at a ratio of 1 mmol / g or more, and therefore correspond to the spontaneous heating inhibitor for carbon resources according to the above-described embodiment.

[0059] [Table 1]

[0060] Next, a spontaneous heating evaluation test was conducted. The following samples were prepared: 1.00 g of carbon resource alone, 0.95 g of carbon resource with 5% by mass (50 mg) of HS added, the same amount of carbon resource with 5% by mass (50 mg) of HI-TS added, and the same amount of carbon resource with 5% by mass (50 mg) of TI added (Comparative Example).

[0061] Next, 1 g of these samples was taken and loaded into the sample cell of the spontaneous heating evaluation device. The sample cell was then placed in the sample holder chamber, and the atmosphere inside the device was replaced with nitrogen. The sample temperature was then raised to 130°C under the nitrogen atmosphere. The sample temperature was measured using a thermocouple. The atmosphere inside the device was then switched from nitrogen to oxygen, and the test began, and the temperature behavior of the sample was measured. The results are shown in Figure 1.

[0062] In FIG. 1, the horizontal axis indicates the elapsed time (min) from the start of the spontaneous heating evaluation test, and the vertical axis indicates the sample temperature. Graph L1 shows the test results when the sample is made of only carbon resources, graph L2 shows the test results when the sample is made of carbon resources to which 5% by mass of HS has been added, graph L3 shows the test results when the sample is made of carbon resources to which 5% by mass of HI-TS has been added, and graph L4 shows the test results when the sample is made of carbon resources to which 5% by mass of TI has been added.

[0063] As is clear from graphs L1 to L4, when the spontaneous heating inhibitor for carbon resources according to the above embodiment, i.e., HS or HI-TS, was added to the carbon resource, a significant spontaneous heating suppression effect was obtained, such as a longer time to heat up to a given temperature or a lower temperature rise over a certain period, and the reproducibility was also high. In particular, a greater effect was obtained when HI-TS was added.

[0064] Example 2 In this example, an experiment similar to that in Example 1 was carried out to examine the time required to reach 200°C when the amount of spontaneous heat generation inhibitor added was changed. The carbon resource to be suppressed from spontaneous heating was the above-mentioned 10 g of acacia-derived wood biomass charcoal, to which additive (HS), additive (HI-TS), and additive (TI) were added in amounts of 1, 3, or 5 mass%.

[0065] The spontaneous heating evaluation test described above was carried out on these samples. The time from the start of the test until the sample temperature reached 200°C (time to reach 200°C) was measured. The results are shown in Table 2.

[0066] From Table 2, it can be seen that a significant effect can be obtained by adding 1 mass % or more of the spontaneous heat generation inhibitor for carbon resources according to this embodiment to the carbon resource.

[0067] [Table 2]

[0068] Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that a person skilled in the art to which the present invention pertains can conceive of various modified or altered examples within the scope of the technical ideas set forth in the claims, and it is understood that these also naturally fall within the technical scope of the present invention. [Industrial Applicability]

[0069] According to the present disclosure, it is possible to provide a spontaneous heat generation inhibitor for carbon resources that can more reliably suppress spontaneous heat generation of carbon resources. Furthermore, according to the present disclosure, it is possible to provide a method for suppressing spontaneous heat generation of carbon resources and a method for storing carbon resources that can more reliably suppress spontaneous heat generation of carbon resources. Therefore, the invention according to the present disclosure is extremely useful industrially.

Claims

1. Contains naphthenic ring carbon atoms in a ratio of 1 mmol / g or more; A spontaneous heat generation inhibitor for carbon resources.

2. Contains naphthenic ring carbon atoms in a ratio of 5 mmol / g or more; The spontaneous heat generation inhibitor for carbon resources according to claim 1 .

3. The naphthenic ring having the naphthenic ring carbon atom has an unsaturated carbon bond. The spontaneous heat generation inhibitor for carbon resources according to claim 1 or 2.

4. the unsaturated carbon bond is an aromatic carbon bond; The spontaneous heat generation inhibitor for carbon resources according to claim 3 .

5. The compound has a fused ring structure in its molecular structure, and a naphthenic ring carbon atom is contained in the fused ring structure. The spontaneous heat generation inhibitor for carbon resources according to claim 1 or 2.

6. A mixture of molecular weights of 200 to 1000. The spontaneous heat generation inhibitor for carbon resources according to claim 1 or 2.

7. It is solid at room temperature, The spontaneous heat generation inhibitor for carbon resources according to claim 1 or 2.

8. The spontaneous heat generation inhibitor for carbon resources according to claim 1 or 2 is added in an amount of 1 mass% or more relative to the carbon resource. A method for suppressing spontaneous heat generation of a carbon resource, comprising:

9. Storing the mixture obtained by the method for suppressing spontaneous heat generation of a carbon resource according to claim 8. A method for storing carbon resources, comprising: