Porous carbon material and method for producing same

Abstract

To provide a porous carbon material with a high gas-adsorption force, capable of easily desorbing gas.SOLUTION: The porous carbon material has the maximum peak of its pore diameter in a range of 4 nm or below, present on the pore diameter distribution curve obtained by the nonlocal density functional theory and has volume elasticity of 500 MPa or below.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a porous carbon material and a method for producing the same. [Background technology]

[0002] Porous carbon materials having a plurality of pores are capable of adsorbing gases and are therefore used in heat pumps. Examples of conventional porous carbon materials that can be used in heat pumps include activated carbon and the porous carbon material disclosed in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5145496 Summary of the Invention [Problem to be solved by the invention]

[0004] However, activated carbon and the porous carbon material disclosed in Patent Document 1 have a problem in that they are low in flexibility and therefore require a relatively large amount of energy to desorb the adsorbed gas. An object of the present invention is to provide a porous carbon material having a high gas adsorption power and easy desorption, and a method for producing the same. Another object of the present invention is to provide an adsorption material having a high gas adsorption power and easy desorption, and a high-performance heat pump and air conditioner including the adsorption material. [Means for solving the problem]

[0005] A porous carbon material according to one embodiment of the present invention has a maximum pore size peak in a range of 4 nm or less in a pore size distribution curve obtained by a delocalized density functional theory, and has a bulk modulus of 500 MPa or less. A method for producing a porous carbon material according to another embodiment of the present invention includes a carbon coating step of using alumina having a plurality of pores as a template and coating the template with carbon to obtain a carbon-coated template, a template removal step of removing the template from the carbon-coated template obtained by the carbon coating step to obtain a carbon structure having a plurality of pores, and a pressurizing step of applying pressure to the carbon structure obtained by the template removal step to reduce the pore diameters of the pores in the carbon structure, thereby obtaining the porous carbon material according to the above-mentioned embodiment.

[0006] An adsorbent material according to yet another aspect of the present invention is an adsorbent material capable of adsorbing a gas, comprising the porous carbon material according to the above aspect. A heat pump according to yet another aspect of the present invention is an adsorption heat pump including an adsorber that adsorbs a working medium gas, and the adsorber includes the adsorption material according to the yet another aspect. An air conditioner according to yet another aspect of the present invention includes the heat pump according to the above-mentioned yet another aspect. Effect of the Invention

[0007] The porous carbon material according to the present invention has a high gas adsorption power and is easy to desorb. The method for producing a porous carbon material according to the present invention can produce a porous carbon material having a high gas adsorption power and is easy to desorb. The adsorbent material according to the present invention has a high gas adsorption power and is easy to desorb. The heat pump and air conditioner according to the present invention are high performance. [Brief description of the drawings]

[0008] [Figure 1] 1 is a formula for calculating a pore size distribution curve by the non-localized density functional method. [Diagram 2] 1 shows adsorption isotherms of porous carbon materials of Examples and Comparative Examples. [Diagram 3] 2 shows pore size distribution curves of porous carbon materials of Examples and Comparative Examples. [Figure 4]FIG. 2 is a diagram showing the results of analyzing the porous carbon materials of Examples and Comparative Examples by X-ray diffraction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] An embodiment of the present invention will be described below. Note that this embodiment is merely an example of the present invention, and the present invention is not limited to this embodiment. In addition, various modifications and improvements can be made to this embodiment, and such modifications and improvements can also be included in the present invention.

[0010] The porous carbon material according to this embodiment has a maximum pore size peak in a range of 4 nm or less in a pore size distribution curve obtained by a delocalized density functional theory, and has a bulk modulus of 500 MPa or less. Since the maximum peak of the pore diameter is within a range of 4 nm or less in the pore diameter distribution curve obtained by the delocalized density functional theory, the pores in the porous carbon material have a small pore diameter, and therefore the porous carbon material according to this embodiment has a high gas adsorption power.

[0011] In addition, since the bulk modulus is 500 MPa or less, the porous carbon material according to this embodiment has high flexibility, and therefore the adsorbed gas can be easily desorbed by applying pressure, enabling efficient adsorption and desorption. Although the smaller the pore size of a porous carbon material, the lower its flexibility tends to be, the porous carbon material according to the present embodiment has both a small pore size and high flexibility, and therefore has a high gas adsorption power and is easy to desorb.

[0012] The type of gas that can be adsorbed by the porous carbon material according to the present embodiment is not particularly limited. For example, nitrogen gas (N 2 ), oxygen gas (O 2 ), hydrogen gas (H 2 ), chlorine gas (Cl 2 ), fluorine gas (F 2 ), carbon monoxide (CO), carbon dioxide (CO 2), nitric oxide (NO), nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ), helium (He), argon (Ar), xenon (Xe), water vapor (H 2 O), alcohol, ammonia (NH 3 ) etc.

[0013] Due to these properties, the porous carbon material according to this embodiment can be used as an adsorbent material for adsorbing gases, heat pumps, and air conditioners. In addition, because of its high specific surface area, electrical conductivity, and corrosion resistance, it can also be used as a catalyst carrier, an electrode material, and a conductive assistant. The porous carbon material according to the present embodiment is made of carbon (C), but may contain elements other than carbon. The carbon content in the porous carbon material is preferably 80% by mass or more, more preferably 95% by mass or more, and even more preferably 98% by mass or more.

[0014] The porous carbon material according to this embodiment will be described in further detail below. [Regarding pore size] The porous carbon material according to the present embodiment is a porous body having a plurality of pores, and in a pore size distribution curve (graph with pore volume on the vertical axis and pore size on the horizontal axis) obtained by the delocalized density functional theory, the maximum peak of the pore size is within a range of 4 nm or less. A porous carbon material having a maximum peak of the pore size within a range of 4 nm or less has a high gas adsorption power. In the pore size distribution curve, the maximum peak of the pore size is preferably within a range of 1.2 nm to 4 nm, more preferably within a range of 1.2 nm to 3.6 nm, and even more preferably within a range of 2.7 nm to 3.6 nm.

[0015] In the porous carbon material according to the present embodiment, the pore size distribution curve is calculated by the delocalized density functional method. That is, when the pores are slit-type, the pore size distribution curve f(H) is assumed by the calculation formula shown in Fig. 1, and the theoretical isotherm ρ(P,H) corresponding to the pore size distribution curve is integrated to calculate the ideal adsorption isotherm IAE(P). Then, the adsorption isotherm obtained by experiment is fitted to the ideal adsorption isotherm IAE(P) so that the error of the adsorption amount is minimized, whereby the pore size distribution curve of the porous carbon material can be calculated.

[0016] [Bulk modulus] The porous carbon material according to this embodiment has a low bulk modulus of 500 MPa or less, and therefore has high flexibility. If the bulk modulus is 500 MPa or less, the specific surface area and pore volume of the porous carbon material are also large. The bulk modulus of the porous carbon material is preferably 300 MPa or less, more preferably 250 MPa or less, and even more preferably 150 MPa or less. The bulk modulus of the porous carbon material according to this embodiment is preferably 50 MPa or more. The bulk modulus of the porous carbon material according to this embodiment can be measured, for example, by mercury porosimetry.

[0017] [Spectra obtained by X-ray diffraction method] In the porous carbon material according to this embodiment, in a spectrum obtained by X-ray diffraction, the ratio of the peak intensity of the carbon (002) plane to the peak intensity of the carbon (10) plane is preferably 1.3 to 4 times, more preferably 1.3 to 2 times. The peak intensity of the (002) plane represents the degree of development of the carbon layered structure, and the peak intensity of the (10) plane represents the degree of development of the carbon hexagonal mesh plane. Therefore, if the ratio of the peak intensity of the (002) plane of carbon to the peak intensity of the (10) plane of carbon is 1.3 to 4 times, it indicates that the carbon layered structure is developed and the pore diameter of the pores is small. However, if the carbon layered structure is too developed, there is a risk that the pore volume will become small.

[0018] [Adsorption isotherm] The porous carbon material according to this embodiment preferably has an adsorption isotherm (a graph in which the vertical axis represents the amount of gas adsorbed (converted into the amount of adsorption under standard conditions) and the horizontal axis represents the relative pressure (the ratio p / p0 of the adsorption equilibrium pressure p and the saturated vapor pressure p0)) obtained by adsorbing, for example, nitrogen gas, which exhibits IUPAC type I classification. If the adsorption isotherm is IUPAC type I classification, gas adsorption is possible even at low pressure. Furthermore, if the adsorption isotherm is IUPAC type I classification, there is little change in adsorption and desorption characteristics due to temperature.

[0019] [About density] The density of the porous carbon material according to this embodiment is 0.5 g / cm 3 It is preferable that the concentration is 0.5 g / cm or more. 3 More than 1.1g / cm 3 More preferably, it is 0.5 g / cm or less. 3 More than 0.7g / cm 3 The porous carbon material according to this embodiment has a high density because it has many pores with small pore diameters. 3 If it is less than this, the pore volume is large, which is more preferable.

[0020] [Method of producing porous carbon material] The method for producing the porous carbon material according to the present embodiment is not particularly limited, but the porous carbon material according to the present embodiment can be produced, for example, by the following method. That is, the method for producing the porous carbon material according to the present embodiment is to form a porous carbon material by using alumina (Al 2 O 3 The method includes a carbon coating step of using the carbon-coated mold (a) as a template and coating the template with carbon to obtain a carbon-coated template, a template removal step of removing the template from the carbon-coated template obtained in the carbon coating step to obtain a carbon structure having a plurality of pores, and a pressurizing step of applying pressure to the carbon structure obtained in the template removal step to reduce the pore diameters of the pores in the carbon structure to obtain a porous carbon material.

[0021] In the carbon coating step, the method for coating the surface of the alumina template with carbon is not particularly limited, but may be, for example, a chemical vapor deposition method. The type of organic compound used as a carbon source in the chemical vapor deposition method is not particularly limited, but a compound that is thermally decomposed by heating is preferred. Examples of organic compounds used as carbon sources in chemical vapor deposition include hydrocarbon compounds and alcohols, and specific examples of these include benzene (C 6 H 6 ), toluene (C 7 H 8 ), acetylene (C 2 H 2 ), ethylene (C 2 H 4 ), propylene (C 3 H 6 ), methane (CH 4 ), ethane (C 2 H 6 ), methanol (CH 3 OH), ethanol (C 2 H 5 OH).

[0022] The template removal step is a step of obtaining a carbon structure, which is a precursor of the porous carbon material according to the present embodiment, by removing only the template from the carbon-coated template, and by using alumina as the template, a carbon structure having pores reflecting the microstructure of the template is obtained. The method of removing the template in the template removal step is not particularly limited, and examples thereof include a method of dissolving the template with an acid or alkali.

[0023] Examples of acids are hydrofluoric acid (HF), hydrochloric acid (HCl), and sulfuric acid (H 2 SO 4 ), nitric acid (HNO 3 Examples of alkali include sodium hydroxide (NaOH), potassium hydroxide (KOH), lithium hydroxide (LiOH), rubidium hydroxide (RbOH), and cesium hydroxide (CsOH).

[0024] The pressurizing step is a step of applying pressure to the carbon structure to reduce the pore size of the pores in the carbon structure, thereby obtaining the porous carbon material according to the present embodiment. The method of applying pressure to the carbon structure is not particularly limited as long as it can reduce the pore size of the pores in the carbon structure, and may be, for example, a hot press method.

[0025] The pressure applied to the carbon structure is preferably 30 MPa or more and 345 MPa or less, more preferably 30 MPa or more and 150 MPa or less, and even more preferably 30 MPa or more and 60 MPa or less. The pressurizing step may be carried out at a high temperature, and the temperature is preferably 200°C or more and more preferably 200°C or more and 600°C or less.

[0026] The material of the template used in producing the porous carbon material is preferably alumina, but it is also possible to use a template made of other materials, for example, magnesium oxide. A heat treatment step may be provided between the mold removal step and the pressure step. By subjecting the carbon structure obtained in the mold removal step to a heat treatment before the pressure step, the crystallinity of carbon can be increased, and a porous carbon material having higher electrical conductivity, corrosion resistance, and specific surface area can be obtained. The temperature of the heat treatment is not particularly limited as long as the crystallinity of carbon can be increased, but is preferably 1750°C or higher and 1850°C or lower, and more preferably 1770°C or higher and 1830°C or lower.

[0027] [About adsorption materials] The porous carbon material according to the present embodiment has a high adsorption power for gases that are adsorbates (e.g., water vapor, alcohol vapor) and is easy to desorb and therefore can be used as an adsorption material for adsorbing gases. That is, the adsorption material according to the present embodiment is an adsorption material capable of adsorbing gases, and includes the porous carbon material according to the present embodiment. Thus, the adsorption material according to the present embodiment has a high adsorption power for gases and is easy to desorb and absorb. The adsorption material according to the present embodiment may be made of only the porous carbon material according to the present embodiment, or may be made of the porous carbon material according to the present embodiment and a member made of another material.

[0028] [About heat pumps] The adsorbent material according to the present embodiment has a high gas adsorption power and is easy to adsorb and desorb, and therefore can be used in a heat pump. That is, the heat pump according to the present embodiment is an adsorption-type heat pump including an adsorber that adsorbs a gas working medium, and the adsorber includes the adsorbent material according to the present embodiment. The heat pump according to the present embodiment has high performance because it can efficiently adsorb and desorb gas of a working medium (e.g., water, alcohol). For the heat pump according to the present embodiment, it is preferable to use a porous carbon material whose adsorption force does not change significantly over a wide temperature range.

[0029] [About the air conditioner] The heat pump according to the present embodiment is capable of efficiently adsorbing and desorbing the working medium gas and has high performance, and therefore can be used in an air conditioner. That is, the air conditioner according to the present embodiment includes the heat pump according to the present embodiment. The air conditioner according to the present embodiment is capable of efficiently adsorbing and desorbing the working medium gas and has high performance. EXAMPLES

[0030] The present invention will be described more specifically below with reference to examples and comparative examples. Example 1 <Carbon coating process> Alumina powder (Alumina TM300 manufactured by Taimei Chemical Industry Co., Ltd., crystal phase: γ-alumina, average particle size: 7 nm, specific surface area: 220 m 2 A pellet molder (Shimadzu Corporation KBr tablet molder P / N202-32010, diameter: 13 mm) was filled with 0.2 g of the alumina pellets. A pressure of 591 MPa was applied to the pellets using a hydraulic jack at room temperature and the pellets were held for 10 seconds. The pellet molder was then turned upside down and pressure was applied in the same manner to produce alumina pellets. The porosity of the alumina pellets was 53%, and the density was 1.9 g / cm. 3 It was.

[0031] The alumina pellets thus produced may have glycerin applied to the pellet molding machine to prevent adhesion of the alumina powder, so the alumina pellets were heat-treated in a muffle furnace to remove the glycerin and sinter. Specifically, the alumina pellets were placed on a silicon plate, placed in a muffle furnace, and heated to 900°C in air at a heating rate of 5°C / min, and held at 900°C for 2 hours, thereby subjecting the alumina pellets to heat treatment. The porosity of the heat-treated alumina pellets was 60%, and the density was 1.6 g / cm. 3 It was.

[0032] Next, the heat-treated alumina pellets were placed in a reaction tube with an inner diameter of 17 mm, and the surfaces of the alumina particles were coated with carbon by chemical vapor deposition in the reaction tube. Propylene was used as the carbon source for the chemical vapor deposition. Specifically, the alumina pellets were heated while nitrogen gas was flowing into the reaction tube at a flow rate of 54 mL / min, and the temperature was increased from room temperature to 700°C at a heating rate of 10°C / min, and the pellets were held at 700°C for 30 minutes.

[0033] After that, a mixture of carrier gas and propylene was introduced into the reaction tube, and chemical vapor deposition was carried out at 700℃ for 2 hours. Nitrogen gas was used as the carrier gas, and the proportion of propylene in the mixed gas was 20% by volume. The flow rate of propylene during chemical vapor deposition was 11mL / min, and the flow rate of nitrogen gas was 43mL / min. After the chemical vapor deposition was completed, the introduction of propylene was stopped and the flow rate of nitrogen gas was changed to 54 mL / min.Then, the temperature was kept at 700°C for 30 minutes under the flow of nitrogen gas, and then cooled to obtain alumina pellets in which the surfaces of the alumina particles were coated with carbon.

[0034] <Mold removal process> Next, the alumina particles were dissolved in an alkaline solution to remove the alumina particles, which were the template, from the carbon-coated alumina particles. Alumina pellets with the surfaces of the alumina particles coated with carbon and a 5 mol / L aqueous sodium hydroxide solution (50 times or more the stoichiometric ratio) were placed in a Teflon (registered trademark) autoclave vessel, and the temperature was raised to 250°C at a heating rate of 250°C / h using a muffle furnace. After being held at 250°C for 2 hours, the vessel was naturally cooled, and the contents of the autoclave vessel were filtered. The filtered powder was vacuum dried at 150°C for 6 hours to obtain a carbon structure (alumina template carbon) having pores reflecting the fine shape of the template.

[0035] <Pressing process> The carbon structure obtained in the mold removal step was filled into the cylindrical internal space of a jig (a pellet-making mold manufactured by Mitsubiki Kogyo Co., Ltd., outer diameter 30 mm, inner diameter 10 mm, length 50 mm), and the jig was set in a hot press device. A stress of 30 MPa was applied to the carbon structure in the internal space of the jig for 3 hours, during which the temperature was raised and heated. That is, the temperature was raised from room temperature to 600°C over 2 hours, and the temperature was maintained at 600°C for 1 hour. After the hot press was completed, the porous carbon material was naturally cooled to obtain a pellet-shaped porous carbon material.

[0036] <Analysis of porous carbon materials> The pellets of the porous carbon material produced as described above were subjected to various analyses. That is, the pore size distribution curve, the adsorption isotherm, and the X-ray diffraction spectrum were obtained, and the bulk modulus and density were measured. These methods are described below.

[0037] <Pore size distribution curve, adsorption isotherm> First, the pellets of the porous carbon material were pretreated by vacuum drying at 150 °C for 6 hours. Then, using a high-precision automatic gas / vapor adsorption measurement device (BEL SORP MAX manufactured by BEL Japan, Inc.), nitrogen gas was adsorbed onto the pretreated pellets at a temperature of -196 °C to obtain an adsorption isotherm. The results are shown in Figure 2. As described above, the pore size distribution curve was calculated by the non-local density functional method. That is, the pore size distribution curve f(H) was assumed according to the calculation formula shown in Figure 1, and the ideal adsorption isotherm IAE(P) was calculated by integrating the theoretical isotherm ρ(P,H) corresponding to the pore size distribution curve. Then, the adsorption isotherm obtained as described above was fitted to the ideal adsorption isotherm IAE(P) so that the error in the adsorption amount was minimized, thereby calculating the pore size distribution curve of the porous carbon material. The results are shown in Figure 3.

[0038] <X-ray diffraction spectrum> Using an X-ray diffractometer XRD-6100 manufactured by Shimadzu Corporation, X-ray diffraction measurement of the pellets of the porous carbon material was performed. The pellets of the porous carbon material were placed on a silicon non-reflecting plate and set in the X-ray diffractometer. The X-ray source was Cu-Kα, the voltage was 40 kV, and the current was 30 mA. Then, the ratio of the peak intensity of the (002) plane of carbon to the peak intensity of the (10) plane of carbon was calculated and graphed. The results are shown in Figure 4.

[0039] <Bulk modulus> First, the pellets of the porous carbon material were pretreated by vacuum drying at 100 °C for 3 hours. Then, using a mercury porosimeter AutoPore IV9510 type manufactured by Micromeritics, the bulk modulus of the pretreated pellets was measured. The method will be described below.

[0040] The pellets and mercury were placed in a sealed container, and then pressure was applied. The volume change of the mercury at that time was regarded as the volume change of the pellets and measured. However, since the mercury enters the pores of the pellets, care was taken not to regard the volume change caused thereby as the volume change of the pellets. The pressure range to be measured is from about 3 kPa to 413 MPa. The relationship between the mercury pressure P during mercury injection and the pore radius r is expressed by the following formula, where γ is the surface tension of mercury (485 mN / m) and θ is the contact angle between the mercury and the pellet wall (130°). P = -(2πrγ cosθ) / (πr 2 ) r=-(2γ cosθ) / P

[0041] When a sample has a volume of V under pressure P and a pressure of P+ΔP is applied, causing the volume to become V+ΔV, the following relationship holds using the bulk modulus κ: ΔP=-κΔV / V(ΔP>0, ΔV<0) Using the above measurement results (pressure and volume change), a graph of ΔP=-κΔV / V was created. The bulk modulus was calculated from the slope of the relatively gentle slope immediately after the initial steep rise (range where the mercury pressure is low) of the obtained curve.

[0042] <density> The mass of the pellet of the porous carbon material was measured and divided by the volume of the pellet (the product of the base area and thickness of the cylindrical pellet) to calculate the density of the porous carbon material. As can be seen from the pore size distribution curve in Fig. 3, the maximum peak of the pore size of the porous carbon material of Example 1 was 3.6 nm. Also, as can be seen from the adsorption isotherm in Fig. 2, the adsorption isotherm of the porous carbon material of Example 1 showed Type I in the IUPAC classification. Furthermore, as can be seen from the X-ray diffraction spectrum in Fig. 4, the porous carbon material of Example 1 had a ratio of the peak intensity of the carbon (002) plane to the peak intensity of the carbon (10) plane of 1.7 times. Furthermore, the bulk modulus of the porous carbon material of Example 1 was 120 MPa, and the density was 0.51 g / cm. 3 These results are summarized in Table 1.

[0043] [Table 1]

[0044] As shown in Table 1, the porous carbon material of Example 1 has a small pore diameter and therefore has a high gas adsorption power. In addition, since the bulk modulus is 500 MPa or less and the material is highly flexible, the adsorption of the adsorbed gas does not require a large amount of energy and is easy to desorb. Furthermore, since the adsorption isotherm shows the IUPAC type I classification, the change in adsorption and desorption characteristics due to temperature is small.

[0045] [Examples 2, 3, and 4] The porous carbon materials of Examples 2, 3, and 4 were produced in the same manner as in Example 1, except that the stress applied to the carbon structure in the hot press was 60 MPa, 150 MPa, and 345 MPa, respectively, as shown in Table 1. The obtained porous carbon materials of Examples 2, 3, and 4 were subjected to various analyses in the same manner as in Example 1. That is, the pore size distribution curve, adsorption isotherm, and X-ray diffraction spectrum were obtained, and the bulk modulus and density were measured. These results are summarized in Table 1. As shown in Table 1, the porous carbon materials of Examples 2, 3, and 4 have small pore diameters and therefore have high gas adsorption power. In addition, since the bulk modulus is 500 MPa or less and the materials are highly flexible, the desorption of the adsorbed gas does not require a large amount of energy and is easy. Furthermore, since the adsorption isotherm shows Type I of the IUPAC classification, the change in adsorption and desorption characteristics due to temperature is small.

[0046] Comparative Example 1 For the carbon structure obtained by carrying out the heat treatment step in Example 1 (but not the pressurizing step), the pore size distribution curve, adsorption isotherm, and X-ray diffraction spectrum were obtained, and the bulk modulus and density were measured in the same manner as in Example 1. These results are summarized in Table 1. As shown in Table 1, the carbon structure of Comparative Example 1 had a bulk modulus of 500 MPa or less and was highly flexible, but had a larger pore size than the porous carbon material of Example 1. Therefore, the gas adsorption power was lower than that of the porous carbon material of Example 1. In addition, the adsorption isotherm showed type IV of the IUPAC classification, and therefore the adsorption and desorption characteristics changed significantly with temperature.

[0047] Comparative Example 2 For a commercially available activated carbon (activated carbon M30 manufactured by Osaka Gas Chemicals Co., Ltd.), the pore size distribution curve, adsorption isotherm, and X-ray diffraction spectrum were obtained, and the bulk modulus and density were measured in the same manner as in Example 1. These results are summarized in Table 1. As shown in Table 1, the activated carbon of Comparative Example 2 has a small pore diameter and high gas adsorption power, but has a bulk modulus of more than 500 MPa and low flexibility, so that a large amount of energy is required to desorb the adsorbed gas.

[0048] [Comparative Examples 3 and 4] A porous carbon material was produced as follows using zeolite as a template. The zeolite used as the template was silicon dioxide (SiO 2 ) and alumina, and is a Na-type Y-type zeolite with a ratio of silicon dioxide to alumina (silicon dioxide / alumina) of 5.6 (manufactured by Tosoh Corporation). This zeolite was vacuum dried at 150°C for 4 hours, and then furfuryl alcohol (C 5 H 6 O 2 ) was added to the zeolite to impregnate it into the pores of the zeolite. Next, the zeolite impregnated with furfuryl alcohol was mixed with mesitylene (C 9 H 12 After washing and filtering, the mixture was heated to 150°C under a nitrogen gas atmosphere to polymerize furfuryl alcohol within the pores of the zeolite, resulting in a composite of poly(furaryl alcohol) and zeolite.

[0049] The composite was heated to 700°C at a heating rate of 5°C / min in a nitrogen gas atmosphere. As soon as the temperature reached 700°C, a gas containing propylene at a concentration of 2.0% by volume was introduced. Chemical vapor deposition was then carried out at 700°C for 1 hour to further laminate a carbon film within the pores of the zeolite. Thereafter, the introduction of the propylene-containing gas was stopped, and the composite was heated to 900°C at a heating rate of 5°C / min in a nitrogen gas atmosphere, held at that temperature for 3 hours, and then allowed to cool.

[0050] Next, the composite that had been subjected to chemical vapor deposition was immersed in hydrofluoric acid to dissolve the zeolite in the hydrofluoric acid and remove the zeolite from the composite. This resulted in the production of zeolite-templated carbon. This zeolite-templated carbon was used as the porous carbon material of Comparative Example 3. Next, pressure was applied to the zeolite-templated carbon obtained as described above to reduce the pore size of the pores in the zeolite-templated carbon, thereby obtaining a porous carbon material of Comparative Example 4. The method of applying pressure was the same as in Example 1. However, the stress applied to the zeolite-templated carbon in the hot press was 148 MPa.

[0051] For the porous carbon materials of Comparative Examples 3 and 4, the pore size distribution curves, adsorption isotherms, and X-ray diffraction spectra were obtained, and the bulk modulus and density were measured in the same manner as in Example 1. These results are summarized in Table 1. As shown in Table 1, the porous carbon materials of Comparative Examples 3 and 4 have small pore diameters and high gas adsorption power, but have low flexibility with bulk modulus exceeding 500 MPa, so that a large amount of energy is required to desorb the adsorbed gas.

Claims

1. A porous carbon material having a maximum pore size peak in a range of 4 nm or less in a pore size distribution curve obtained by a delocalized density functional method, and having a bulk modulus of 500 MPa or less.

2. 2. The porous carbon material according to claim 1, wherein the maximum peak of the pore diameter is within a range of 1.2 nm or more and 4 nm or less.

3. 3. The porous carbon material according to claim 1, wherein in a spectrum obtained by X-ray diffraction, the ratio of the peak intensity of the (002) plane of carbon to the peak intensity of the (10) plane of carbon is 1.3 to 4 times.

4. 3. The porous carbon material according to claim 1, wherein in a spectrum obtained by X-ray diffraction, the ratio of the peak intensity of the (002) plane of carbon to the peak intensity of the (10) plane of carbon is 1.3 to 2 times.

5. 5. The porous carbon material according to claim 1, wherein an adsorption isotherm obtained by adsorbing nitrogen gas shows Type I in the IUPAC classification.

6. Density is 0.5 g / cm 3 The porous carbon material according to any one of claims 1 to 5.

7. Density is 0.5 g / cm 3 0.7g / cm or more 3 The porous carbon material according to any one of claims 1 to 5, wherein the porous carbon material has a molecular weight of less than 1000.

8. a carbon coating step of using alumina having a plurality of pores as a template and coating the template with carbon to obtain a carbon-coated template; a template removal step of removing the carbon-coated template obtained in the carbon coating step to obtain a carbon structure having a plurality of pores; a pressurizing step of applying pressure to the carbon structure obtained by the template removing step to reduce the pore diameter of the pores in the carbon structure, thereby obtaining the porous carbon material according to any one of claims 1 to 7; A method for producing a porous carbon material having the above structure.

9. An adsorbent material capable of adsorbing a gas, comprising the porous carbon material according to any one of claims 1 to 7.

10. An adsorption heat pump comprising an adsorber for adsorbing a gaseous working medium, the adsorber comprising the adsorption material according to claim 9.

11. An air conditioner comprising the heat pump according to claim 10.

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