Carbonaceous material and its manufacturing method, adsorption filter, water purifier cartridge, water purifier, and water purification equipment

Abstract

To provide a carbonaceous material capable of removing a wide range of harmful substances, from chloroform having a relatively small molecular size to an anionic surfactant having a relatively large molecular size, with equivalent performance, and a manufacturing method thereof, an adsorption filter, a water purifier cartridge, a water purifier, and a water purification facility. The carbonaceous material of the present invention has a pore volume of 0.16 cm per 1 g of the carbonaceous material, the volume being calculated from the nitrogen adsorption isotherm by the QSDFT method. 3 / g or more 0.30cm 3 / g or less, the iodine adsorption amount is 750 mg / g or more and 1,340 mg / g or less, and the Reactive Black 5 value is 6.0 g / L or more and 67.0 g / L or less.

Description

[Technical field]

[0001] The present invention relates to a carbonaceous material and a method for producing the same, an adsorption filter, a water purifier cartridge, a water purifier, and a water purification facility. [Background technology]

[0002] Home water purifiers are widely used to remove harmful substances from tap water. Among these harmful substances, volatile organic compounds such as trihalomethanes, including chloroform, which are present in trace amounts in tap water, and harmful substances such as musty odors, typified by 2-methylisoborneol (2-MIB), are designated as substances to be removed by home water purifiers under the Household Products Quality Labeling Act, and it is desirable to remove them from tap water.

[0003] In order to remove such harmful substances, carbonaceous materials are usually used in household water purifiers. For example, Patent Document 1 describes a carbonaceous material having a benzene adsorption amount of 25% to 40%, a vitamin B12 adsorption amount of 13.0 mg / g to 50.0 mg / g, and a mesopore volume of 0.070 cm3 calculated by the BJH method from the nitrogen adsorption isotherm. 3 / g or more 0.150cm 3 / g or less. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2020 / 218370 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the carbonaceous material described in Patent Document 1, the pore volume and specific surface area are designed so that it can remove 2-MIB and the like, which have a relatively large molecular size, rather than trihalomethanes such as chloroform, which have a relatively small molecular size. Therefore, although the filtering capacity value for 2-MIB and the like is high, it is difficult to use the carbonaceous material to remove substances with a relatively small molecular size, such as trihalomethanes, and it is extremely difficult to remove chloroform, which has an even smaller molecular size among trihalomethanes.

[0006] Furthermore, in 2019, the JIS test method for home water purifiers was revised, and the new JIS S3201:2019 added five new substances to be removed. This has created a demand for home water purifiers that can remove a wider variety of harmful substances than before.

[0007] Of the five new types, the anionic surfactants have a larger molecular size than 2-MIB. In the carbonaceous materials used in conventional household water purifiers, the pore volume and specific surface area are designed to be suitable for removing molecules of about the same size as 2-MIB, as in Patent Document 1. Therefore, it is difficult for conventional carbonaceous materials to remove harmful substances with larger molecular sizes, such as anionic surfactants.

[0008] Since the JIS test method was revised in this way, carbonaceous materials used in household water purifiers are required to be able to remove a wide range of harmful substances, from relatively small molecular substances such as chloroform to relatively large molecular substances such as anionic surfactants, with equal performance.

[0009] The present invention has been made in view of the above problems, and has an object to provide a carbonaceous material capable of removing a wide range of harmful substances, from chloroform and the like, which have a relatively small molecular size, to anionic surfactants and the like, which have a relatively large molecular size, with equivalent performance, as well as a method for producing the same, an adsorption filter, a water purifier cartridge, a water purifier, and a water purification facility. [Means for solving the problem]

[0010] As a result of intensive research into achieving the above object, the inventors have found that a carbonaceous material having a pore volume, iodine adsorption amount, and Reactive Black pentavalent value each falling within a specific range can remove a wide range of harmful substances, from relatively small molecular size substances such as chloroform to relatively large molecular size substances such as anionic surfactants, with equivalent performance, and have completed the present invention.

[0011] The present invention includes the following embodiments. [1] The pore volume of pores with diameters of 0.70 nm or less per gram of carbonaceous material calculated using the QSDFT method from the nitrogen adsorption isotherm is 0.16 cm 3 / g or more 0.30cm 3 / g or less, an iodine adsorption amount is 750 mg / g or more and 1,340 mg / g or less, and a reactive black pentavalent amount is 6.0 g / L or more and 67.0 g / L or less.

[0012] [2] The carbonaceous material according to [1], wherein the ratio (A / B) of the pore volume (A) of pores having a pore diameter of 1.00 nm or less per 1 g of the carbonaceous material calculated by the QSDFT method from the nitrogen adsorption isotherm to the pore volume (B) of mesopores calculated by the BJH method from the N2 adsorption isotherm at -196°C is 3.0 or more and 8.0 or less.

[0013] [3] The mesopore volume calculated from the N2 adsorption isotherm at -196°C using the BJH method is 0.030 cm 3 / g or more 0.140cm 3 / g or less of the carbonaceous material according to [1].

[0014] [4] The specific surface area calculated by the BET method from the N2 adsorption isotherm at -196°C is 610 m 2 / g or more 1,400m 2 / g or less of the carbonaceous material according to [1].

[0015] [5] The carbonaceous material according to [1], having a packing density measured by a tapping method of 0.36 g / mL or more and 0.60 g / mL or less.

[0016] [6] The carbonaceous material according to any one of [1] to [5], which is used for removing at least chloroform and an anionic surfactant in water.

[0017] [7] A method for producing a carbonaceous material according to any one of [1] to [5], comprising: a carbonization step of carbonizing a raw material to obtain a carbonized material; and an activation step of activating the carbonized material to obtain an activated material.

[0018] [8] The method according to [7], further comprising a washing step of washing the activated material.

[0019] [9] The manufacturing method described in [7], wherein the raw material is coconut shell.

[0020]

[10] An adsorption filter comprising the carbonaceous material according to any one of [1] to [5].

[0021]

[11] A water purifier cartridge comprising the carbonaceous material according to any one of [1] to [5].

[0022]

[12] A water purifier comprising the carbonaceous material according to any one of [1] to [5].

[0023]

[13] A water purification facility comprising the carbonaceous material according to any one of [1] to [5]. Effect of the Invention

[0024] According to the present invention, it is possible to provide a carbonaceous material capable of removing a wide range of harmful substances, from chloroform and the like, which have a relatively small molecular size, to anionic surfactants and the like, which have a relatively large molecular size, with equivalent performance, as well as a manufacturing method thereof, an adsorption filter, a water purifier cartridge, a water purifier, and a water purification facility. [Brief description of the drawings]

[0025] [Figure 1] FIG. 1I is a schematic cross-sectional view of a rotary kiln, and FIG. 1II is a schematic side view of the rotary kiln. [Diagram 2] FIG. 2 is a schematic cross-sectional view for explaining a rotary kiln. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Hereinafter, an embodiment for carrying out the present invention (hereinafter, simply referred to as "the present embodiment") will be described in detail. Note that the following present embodiment is an example for explaining the present invention, and the present invention is not limited to only this embodiment.

[0027] [Carbonaceous material] The carbonaceous material of this embodiment has a pore volume of 0.70 nm or less per 1 g of the carbonaceous material calculated from the nitrogen adsorption isotherm by the QSDFT method of 0.16 cm 3 / g or more 0.30cm 3 / g or less, the iodine adsorption amount is 750 mg / g or more and 1,340 mg / g or less, and the Reactive Black 5 value is 6.0 g / L or more and 67.0 g / L or less.

[0028] By satisfying these requirements, the carbonaceous material can remove a wide range of harmful substances, from chloroform and the like, which have a relatively small molecular size, to anionic surfactants and the like, which have a relatively large molecular size, with equal performance. That is, since the carbonaceous material has a pore volume with a pore diameter of 0.70 nm or less within a specific range, it can have high adsorption performance for chloroform and the like, which have a relatively small molecular size. In addition, since the pore diameter of the carbonaceous material is controlled so as to be suitable for anionic surfactants and the like, which have a relatively large molecular size, it can also have high adsorption performance for anionic surfactants and the like.

[0029] The carbonaceous material can favorably adsorb chloroform and anionic surfactants. In addition, following the revision of the JIS in 2019, volatile organic compounds other than chloroform (bromodichloromethane, dibromochloromethane, bromoform, cis-1,2-dichloroethylene and trans-1,2-dichloroethylene, tetrachloroethylene, trichloroethylene, and benzene) can be tested in place of chloroform using the test method in JIS S3201:2019 Appendix A. Therefore, if the removal performance of chloroform can be satisfied, it can be said that volatile organic substances other than chloroform can also be removed. In other words, the carbonaceous material can suitably adsorb chloroform and one or more of these volatile organic compounds. Examples of anionic surfactants include alkylsulfonates such as linear sodium dodecylbenzenesulfonate, etc. The carbonaceous material can suitably adsorb one or more of these anionic surfactants.

[0030] In carbonaceous materials, the pore volume (cm) of pores with diameters of 0.70 nm or less calculated per 1 g of carbonaceous material by the QSDFT method from the nitrogen adsorption isotherm 3 / g) (hereinafter also referred to simply as "pore volume with a pore diameter of 0.70 nm or less") is 0.16 cm 3 / g or more 0.30cm 3 When the pore volume of pores having a diameter of 0.70 nm or less is in the above range, the carbonaceous material exhibits high removal performance mainly for chloroform and the like. 3 / g or more, the small pore volume effective for removing chloroform and the like, which has a relatively small molecular size, is sufficient within the micropore volume, and the adsorption performance for chloroform and the like is significantly improved. In addition, the pore volume of pores with a diameter of 0.70 nm or less is 0.30 cm 3 / g or less, the amount of pore volume suitable for substances smaller than the molecular size of chloroform, etc. is reduced, and the amount of pore volume suitable for chloroform, etc. is increased accordingly. Therefore, the adsorption performance for chloroform, etc. is significantly improved.

[0031] In this specification, the pores of the carbonaceous material are classified according to the pore size (diameter) of the IUPAC (International Union of Pure and Applied Chemistry) into micropores with a pore size of less than 2.0 nm, mesopores with a pore size of 2.0 nm to 50.0 nm, and macropores with a pore size of more than 50.0 nm. Micropores are smaller than mesopores and are mainly effective for adsorption of chloroform and other substances with relatively small molecular sizes. Mesopores are effective for adsorption of anionic surfactants and other substances with relatively large molecular sizes.

[0032] In this specification, the pore volume of a pore diameter of 0.70 nm or less or a pore diameter of 1.00 nm or less is calculated by the QSDFT method (Quenched Solid Density Functional Theory). The QSDFT method is an analytical method that can calculate the pore size distribution of about 0.5 nm to about 40 nm, which is targeted at the pore size analysis of geometrically and chemically irregular microporous and mesoporous carbons. The QSDFT method is a method that significantly improves the accuracy of pore size distribution analysis because it clearly takes into account the effects of roughness and non-uniformity of the pore surface. For specific measurement and calculation methods of the pore volume of a pore diameter of 0.70 nm or less or a pore diameter of 1.00 nm or less, please refer to the Examples.

[0033] The pore volume of the pores having a diameter of 0.70 nm or less is preferably 0.18 cm 3 / g or more 0.29cm 3 / g or less, more preferably 0.20 cm 3 / g or more 0.28cm 3 / g or less, and more preferably 0.22 cm 3 / g or more 0.27cm 3 / g 3 When the pore volume range of pores with diameters of 0.70 nm or less is within the above range, a carbonaceous material tends to be obtained that has higher adsorption performance for chloroform and the like while maintaining removal performance for anionic surfactants and the like.

[0034] The iodine adsorption amount of the carbonaceous material is not less than 750 mg / g and not more than 1,340 mg / g. The iodine adsorption amount is an index of the surface area of ​​pores present in the carbonaceous material that can physically adsorb chloroform, etc., which have a relatively small molecular size, and anionic surfactants, etc., which have a relatively large molecular size. When the iodine adsorption amount of the carbonaceous material is within the above range, the carbonaceous material can exhibit high removal performance against anionic surfactants, etc., while maintaining removal performance against chloroform, etc. When the iodine adsorption amount of the carbonaceous material is 750 mg / g or more, the pore volume of the carbonaceous material becomes sufficiently large, and the adsorption performance of chloroform, etc. and anionic surfactants, etc. is significantly improved. When the iodine adsorption amount of the carbonaceous material is 1,340 mg / g or less, the pores of the carbonaceous material do not become too large, and it becomes easy to control the pores that adsorb chloroform, etc. and anionic surfactants, etc.

[0035] The amount of iodine adsorption is measured and calculated in accordance with JIS K 1474 (2014). For specific methods of measuring and calculating the amount of iodine adsorption, see the Examples.

[0036] Since it has a higher removal performance against chloroform and the like and anionic surfactants and the like, the iodine adsorption amount is preferably 900 mg / g or more and 1,330 mg / g or less, and more preferably 1,000 mg / g or more and 1,310 mg / g or less.

[0037] The carbonaceous material has a Reactive Black 5 valence of 6.0 g / L or more and 67.0 g / L or less. Reactive Black 5 is a dye represented by the following formula (1) and is also called CI Reactive Black-5.

[0038] [ka]

[0039] Reactive Black 5 has a large molecular weight of 995.88 and a bulky structure, so that the pentavalent value of Reactive Black is an index of the adsorption characteristics of anionic surfactants and the like having a relatively large molecular size. When the pentavalent value of Reactive Black is in the above range, the carbonaceous material exhibits high adsorption performance, particularly for anionic surfactants and the like, while maintaining the removal performance for chloroform and the like. When the pentavalent value of Reactive Black is 6.0 g / L or more, the cumulative pore volume in the large pores of the carbonaceous material does not become too large, and the carbonaceous material can also retain small pores that are effective for chloroform and the like. Therefore, while maintaining the removal performance for chloroform and the like having a relatively small molecular size, the carbonaceous material can exhibit high removal performance for anionic surfactants and the like having a relatively large molecular size. When the pentavalent value of Reactive Black is 67.0 g / L or less, the amount of pores suitable for adsorption of anionic surfactants and the like having a relatively large molecular size increases among the pores of the carbonaceous material. Therefore, the adsorption performance for anionic surfactants and the like is significantly improved.

[0040] The Reactive Black 5 value can be calculated, for example, as follows. That is, first, using an ultraviolet-visible spectrophotometer, the absorbance of a test liquid containing Reactive Black 5 and a residual liquid obtained by mixing a carbonaceous material with the test liquid and allowing the Reactive Black 5 to be sufficiently adsorbed on the carbonaceous material, and then removing the carbonaceous material to which the Reactive Black 5 is adsorbed, are measured under conditions of a wavelength of 594 nm and an optical path length (cell length) of 10 mm. Then, using these absorbances, the remaining rate (%) of Reactive Black 5 contained in the residual liquid and the adsorption amount ( / g) of Reactive Black 5 per 1 g of the carbonaceous material are calculated. Using these values, the Reactive Black 5 value (g / L) is calculated as the amount of carbonaceous material required to remove 99% of the Reactive Black 5 in 1 L of the test liquid. In the measurement of the Reactive Black 5 value, it is preferable to use a carbonaceous material whose 50% particle size (D50) of the cumulative distribution based on volume is adjusted to be 9.0 μm or more and 11.0 μm or less. In this specification, the 50% particle size (D50) refers to a value measured as a volume-based median size using a laser diffraction light scattering particle size distribution measuring device. For specific measurement and calculation methods of Reactive Black pentavalent, see the Examples.

[0041] The pentavalent value of Reactive Black is preferably 6.3 g / L or more and 50.0 g / L or less, more preferably 6.5 g / L or more and 40.0 g / L or less, even more preferably 7.0 g / L or more and 30.0 g / L or less, and even more preferably 7.2 g / L or more and 27.0 g / L or less. When the pentavalent value of Reactive Black is within the above range, a carbonaceous material tends to be obtained that has higher adsorption performance for anionic surfactants and the like while maintaining removal performance for chloroform and the like.

[0042] In a carbonaceous material, the ratio (A) of the pore volume having a pore diameter of 1.0 nm or less calculated by the QSDFT method from the nitrogen adsorption isotherm per 1 g of the carbonaceous material (hereinafter also simply referred to as the "pore volume of pores having a pore diameter of 1.00 nm or less") to the mesopore volume (B) (hereinafter also simply referred to as the "pore volume of mesopores") calculated by the BJH method from the N2 adsorption isotherm at -196°C (A / B, hereinafter also simply referred to as the "mesopore ratio") is preferably 3.0 or more and 8.0 or less, more preferably 3.5 or more and 7.5 or less, and even more preferably 4.0 or more and 7.0 or less.

[0043] The pore volume of pores with a diameter of 1.00 nm or less is an index of small pores that are effective mainly for substances with a relatively small molecular size, such as chloroform. Meanwhile, the pore volume of mesopores is an index of large pores that are effective mainly for substances with a relatively large molecular size, such as anionic surfactants. Therefore, the mesopore ratio is an index showing the balance of performance in the removal performance between chloroform, etc. and anionic surfactants, etc.

[0044] When the mesopore ratio is within the above range, it is possible to remove a wide range of harmful substances, from chloroform, which has a relatively small molecular size, to anionic surfactants, which has a relatively large molecular size, with the same performance. When the mesopore ratio is 3.0 or more, the ratio of large pores effective for removing anionic surfactants, etc. is sufficient, and there is a tendency for high adsorption performance to be exhibited for anionic surfactants, etc. When the mesopore ratio is 8.0 or less, the ratio of small pores effective for removing chloroform, etc. is sufficient, and there is a tendency for high adsorption performance to be exhibited for chloroform, etc. For specific measurement and calculation methods of the mesopore ratio, please refer to the Examples.

[0045] In the carbonaceous material, the pore volume of the mesopores (pore volume of the mesopores) determined by the BJH method from the N2 adsorption isotherm at -196 °C is preferably 0.030 cm 3 / g or more 0.140cm 3 / g or less, and more preferably 0.035 cm 3 / g or more 0.100cm 3 / g or less, and more preferably 0.040 cm 3 / g or more 0.090cm 3 / g or less.

[0046] Mesopore volume is 0.030 cm 3 / g or more, the carbonaceous material can have many relatively large pores that are effective against anionic surfactants, etc. 3 / g or less, the pores of the carbonaceous material do not become too large, and the carbonaceous material can have many pores that are effective for adsorption of chloroform, etc. Therefore, when the pore volume of the mesopores is within the above range, it tends to be possible to achieve a higher level of performance in removing chloroform, etc. and performance in removing anionic surfactants, etc. For specific methods for measuring and calculating the pore volume of the mesopores, see the Examples.

[0047] In the carbonaceous material, the specific surface area determined by the BET method from the N2 adsorption isotherm at -196 °C (hereinafter also simply referred to as "BET specific surface area") is preferably 610 m 2 / g or more 1,400m 2 / g or less, more preferably 800m 2 / g or more 1,300m 2 / g or less, and more preferably 900m 2 / g or more 1,300m 2 / g or less.

[0048] The BET specific surface area is an index showing the degree of activation of a carbonaceous material. When the BET specific surface area is in the above range, the carbonaceous material tends to achieve high removal performance against anionic surfactants and the like while maintaining the removal performance of chloroform and the like. 2 / g or more, the carbonaceous material has a sufficient surface area that contributes to physical adsorption, and tends to have high adsorption performance for chloroform, etc. 2 / g or less, the pores of the carbonaceous material do not become too large, and the carbonaceous material tends to have many pores that are effective for adsorption of anionic surfactants, etc. For specific methods for measuring and calculating the BET specific surface area, see the Examples.

[0049] In the carbonaceous material, the packing density measured by the tapping method (hereinafter, also simply referred to as "packing density") is preferably 0.36 g / mL or more and 0.60 g / mL or less, more preferably 0.40 g / mL or more and 0.58 g / mL or less, and even more preferably 0.44 g / mL or more and 0.55 g / mL or less. When the packing density is in the above range, the carbonaceous material tends to achieve a higher level of adsorption performance for a wide range of harmful substances, from chloroform, etc., which has a relatively small molecular size, to anionic surfactants, etc., which has a relatively large molecular size. When the packing density is 0.36 g / mL or more, the pores of the carbonaceous material do not become too large, and many pores effective for chloroform, etc., anionic surfactants, etc. can be held. Therefore, the carbonaceous material tends to have high adsorption performance for chloroform, etc., anionic surfactants, etc. When the packing density is 0.60 g / mL or less, there tends to be a sufficient number of pores that contribute to physical adsorption. Therefore, the carbonaceous material tends to have higher adsorption performance for chloroform, etc. and anionic surfactants, etc. For specific methods of measuring and calculating the packing density, see the Examples.

[0050] The shape of the carbonaceous material varies depending on the application, and is not particularly limited. Examples of such shapes include powder, lump, crushed, sphere, cylinder, elliptical sphere, distorted, elliptical cylinder, elliptical truncated cone, and polygonal prism such as triangular prism, quadrangular prism, pentagonal prism, and hexagonal prism, rod, thread, pellet such as solid pellet and hollow pellet, crushed such as powder, substrate (sheet), woven cloth (cloth), felt, and block.

[0051] The shape of the carbonaceous material is preferably a shape applicable as a carbonaceous material in a known adsorption filter. Examples of such shapes include crushed shapes such as spheres, elliptical spheres, distorted shapes, rods, threads, pellets, and powders, substrates (sheets), woven fabrics (cloths), fibers, and blocks. These shapes can be appropriately selected according to the specific usage mode. Among these, the shape of the carbonaceous material is preferably crushed, and more preferably powdered, because it has high adsorption performance per unit volume. In the case of a powdered carbonaceous material, the dimensions are not particularly limited, and the particle size, etc. may be appropriately adjusted according to the specific usage mode.

[0052] In this specification, the term "crushed" refers to particles that are not uniform in shape and usually have any shape with corners, and the term "powdered" refers to, for example, fine powder, powder, fine grain, and granular powder, and usually has a 50% particle size (D50) of the cumulative volume distribution of 1 μm or more and 150 μm or less.

[0053] For example, when the carbonaceous material is used as an adsorption filter for a water purifier, the shape is preferably a cylinder or a substrate (sheet), although this varies depending on the application and is not particularly limited. When the carbonaceous material has such a shape, the carbonaceous material tends to be efficiently used as an adsorption filter for a water purifier.

[0054] The carbonaceous material is preferably activated carbon.

[0055] [Method of manufacturing carbonaceous materials] The carbonaceous material of the present embodiment can be obtained by a known production method.

[0056] Examples of such a method include a pyrolysis method, an activation method, a coating method, and a vapor deposition method. The activation method is preferably used as the production method. By using such a production method, the pore volume of pores with diameters of 0.70 nm or less calculated by the QSDFT method from the nitrogen adsorption isotherm per 1 g of the carbonaceous material is 0.16 cm 3 / g or more 0.30cm 3 / g or less, an iodine adsorption amount of 750 mg / g or more and 1,340 mg / g or less, and a reactive black pentavalent amount of 6.0 g / L or more and 67.0 g / L or less tend to be easily produced.

[0057] The method for producing a carbonaceous material according to the present embodiment includes a carbonization step of carbonizing a raw material to obtain a carbonized material, and an activation step of activating the carbonized material to obtain an activated material. The method for producing a carbonaceous material according to the present embodiment preferably includes a washing step of washing the activated material.

[0058] (carbonization process) The method for producing a carbonaceous material includes a carbonization step of carbonizing a raw material to obtain a carbonized material. The raw material is not particularly limited as long as it is a material from which a desired carbonaceous material can be obtained. Examples of the raw material include wood, wood flour, fruit shells such as coconut shells, seeds such as palm kernels, plums, and peaches, by-products during pulp production, bagasse, blackstrap molasses, coal (peat, lignite, brown coal, bituminous coal, etc.), anthracite, petroleum distillation residue components, petroleum pitch, coke, and coal tar, and other plant-based or fossil-based raw materials; various synthetic resins such as phenolic resins, vinyl chloride resins, vinyl acetate resins, melamine resins, urea resins, resorcinol resins, celluloid, epoxy resins, polyurethane resins, polyester resins, acrylic resins, and polyamide resins; synthetic rubbers such as polybutylene, polybutadiene, and polychloroprene; other synthetic wood; and synthetic pulp. These raw materials can be used alone, or two or more types can be mixed in any ratio depending on the required specifications.

[0059] The raw material is preferably a natural product, more preferably coconut shell. By using such a raw material, the pore volume of pores with diameters of 0.70 nm or less calculated by the QSDFT method per 1 g of carbonaceous material from the nitrogen adsorption isotherm is 0.16 cm 3 / g or more 0.30cm 3 / g or less, an iodine adsorption amount of 750 mg / g or more and 1,340 mg / g or less, and a reactive black pentavalent amount of 6.0 g / L or more and 67.0 g / L or less can be more easily produced.

[0060] The raw material may contain additives, etc., as necessary. In addition, the additives, etc. may be added to the carbide, as necessary. Examples of such additives include water, coal tar, anhydrous tar, hard pitch, coal tar-based pitch, and petroleum-based pitch. The additives may be used alone or in combination of two or more. The additives and the like are usually mixed in an amount of 1.0 part by mass or more and 50.0 parts by mass or less per 100 parts by mass of the raw material or the carbide. The total amount of the additives and the like is usually 1 part by mass or more and 100 parts by mass or less per 100 parts by mass of the raw material or the carbide. When mixing the raw material or the carbide with the additives, the amount of oxygen in the raw material or the carbide may be adjusted in advance, as necessary, in the range of 1.0% by mass or more and 20.0% by mass or less per 100% by mass of the raw material or the carbide. The adjustment of the amount of oxygen can be performed, for example, by mixing the raw material or the carbide with oxygen under heating at 150° C. to 300° C.

[0061] In the method for producing a carbonaceous material, the raw material may be crushed or molded before being carbonized. For example, the raw material may be crushed into a powder form using a known crusher before being carbonized, and then carbonized. Alternatively, the raw material may be molded into a pellet form by a known method before being carbonized, and then carbonized.

[0062] When the raw material is in the form of powder, the particle size of the powder (50% particle size of cumulative volume distribution, D50) is preferably 1 μm or more and 150 μm or less.

[0063] The method for carbonizing the raw material is not particularly limited, and examples thereof include a method in which the raw material is heated to 300° C. or higher and 900° C. or lower, preferably 400° C. or higher and 800° C. or lower, under oxygen-free conditions.

[0064] The carbonization time can be appropriately set depending on the raw material and the equipment used for carbonization. The carbonization time is, for example, 15 minutes to 20 hours, preferably 30 minutes to 10 hours, and more preferably 60 minutes to 5 hours. The carbonization process can be carried out using known manufacturing equipment such as a rotary kiln. The carbonization process may be carried out under reduced pressure by excluding air, or may be carried out under a nitrogen atmosphere.

[0065] In the method for producing the carbonaceous material, the carbide may be pulverized into a powder using a known pulverizer. This allows the volume of pores with diameters of 0.70 nm or less per gram of the carbonaceous material to be 0.16 cm3, calculated from the nitrogen adsorption isotherm by the QSDFT method. 3 / g or more 0.30cm 3 / g or less, an iodine adsorption amount of 750 mg / g or more and 1,340 mg / g or less, and a reactive black pentavalent amount of 6.0 g / L or more and 67.0 g / L or less tend to be more easily produced. In the method for producing the carbonaceous material, after pulverizing the charcoal into a powder, additives and the like may be added to the powdered charcoal as necessary and kneaded by a known method, and the kneaded product obtained may be molded by a known method.

[0066] When the carbide is in the form of powder, the particle size of the carbide (50% particle size of cumulative volume distribution, D50) is preferably 1 μm or more and 150 μm or less.

[0067] In the method for producing the carbonaceous material, a carbide, a powdered carbide, a kneaded product, or a powdered kneaded product may be molded into a cylindrical pellet shape using a known method. This allows the volume of pores with a pore diameter of 0.70 nm or less calculated by the QSDFT method from the nitrogen adsorption isotherm per 1 g of the carbonaceous material to be 0.16 cm3. 3 / g or more 0.30cm 3 / g or less, an iodine adsorption amount of 750 mg / g or more and 1,340 mg / g or less, and a reactive black pentavalent amount of 6.0 g / L or more and 67.0 g / L or less tend to be more easily produced. When the carbide is in the form of a cylindrical pellet, the diameter of the cylindrical pellet is preferably 0.1 mm or more and 4.0 mm or less, and the aspect ratio (diameter:height) of the cylindrical pellet is preferably 1:1 to 1:10.

[0068] The carbonization step produces a carbonized material of the raw material.

[0069] The method for producing a carbonaceous material may include a washing step and / or a drying step in which the carbonized material is washed and / or dried after the carbonization step. The conditions in these steps are not particularly limited, and known conditions can be used. The following washing step and drying step may also be referred to.

[0070] (Activation process) The method for producing a carbonaceous material includes an activation step of activating a carbonized material to obtain an activated material.

[0071] As the activation treatment, a known method can be adopted.

[0072] The activation treatment can be carried out using known manufacturing equipment such as a rotary kiln, a fluidized furnace, a sleeve furnace (vertical furnace), etc. The activation treatment may be carried out under reduced pressure by excluding air, or under a nitrogen atmosphere.

[0073] The activation treatment is preferably carried out using a rotary kiln. By using a rotary kiln, the activated material, which becomes lighter as the activation of the carbide progresses, can remain in the kiln without scattering outside the furnace. Therefore, the carbide can be activated more sufficiently, and there is a tendency that an activated material in which micropores and mesopores are sufficiently developed and the ratio of these pores is controlled within a suitable range can be obtained.

[0074] In addition, the use of a rotary kiln makes it possible to efficiently bring the carbide into contact with an active gas, which tends to favorably produce a carbonaceous material having higher adsorption performance for chloroform and anionic surfactants.

[0075] When the activation treatment is performed using a rotary kiln, the carbide fed into the rotary kiln preferably has a particle size of 70 mesh (mesh size: 243 μm) sieve size 2 mesh undersieve (mesh size: 10.7 mm) on a standard sieve wire mesh specified in JIS Z8801-1:2019, and more preferably has a particle size of 32 mesh (mesh size: 490 μm) sieve size 2 mesh undersieve (mesh size: 10.7 mm). By having the particle size of the carbide within the above range, the activated material, which has become lighter in mass as the activation of the carbide progresses, remains in the kiln longer, making it possible to perform activation more efficiently. As the carbide, a carbide whose particle size has been adjusted by cutting the raw material to a desired size before the carbonization process may be used, or a carbide whose particle size has been adjusted by crushing and classifying the carbide to a desired size may be used.

[0076] Examples of the activation method include a gas activation method in which the carbonized material is gasified using an activated gas such as water vapor gas, oxygen gas, and carbon dioxide gas, and a chemical activation method in which the carbonized material is activated using a chemical such as zinc chloride and phosphoric acid. The gas activation method is preferred as the activation method. By using an activated gas as the gas activation method, there is a tendency that the reaction rate is more sufficient and the reaction rate can be controlled without reducing the production efficiency. Therefore, there is a tendency that the carbonaceous material with developed micropores and mesopores can be obtained more easily. As a result, there is a tendency that the carbonaceous material can be suitably produced with a higher level of adsorption performance for a wide range of harmful substances, from chloroform, which has a relatively small molecular size, to anionic surfactants, which has a relatively large molecular size. In addition, an inert gas such as nitrogen may be used in combination with the activated gas.

[0077] The partial pressure of the active gas is, for example, 10% or more and 100% or less, and preferably 30% or more and 100% or less.

[0078] As the active gas, it is preferable to use one or more gases selected from the group consisting of water vapor gas and oxygen gas, and it is more preferable to use both water vapor gas and oxygen gas.

[0079] Water vapor gas has a tendency to have a more sufficient reaction rate and to be able to control the reaction rate more without reducing the production efficiency. In addition, the use of water vapor gas tends to make it easier to obtain a carbonaceous material with developed micropores and mesopores. Therefore, it tends to be possible to suitably produce a carbonaceous material having a higher adsorption performance for chloroform, anionic surfactants, etc.

[0080] In addition, since the activation reaction is usually an endothermic reaction, a certain amount of heat is required to proceed with the activation reaction more efficiently. In order to maintain the amount of heat, it is preferable to use oxygen gas together with water vapor gas as the active gas. The volatile gas generated during the activation reaction reacts with the oxygen gas and burns, making it possible to maintain the amount of heat required for activation. Examples of the volatile gas include flammable gases such as hydrogen gas and carbon monoxide gas generated by activating carbide.

[0081] When water vapor and oxygen gas are used as active gases, the partial pressure of water vapor is 、3 It is more preferable that the oxygen gas partial pressure is 3.0% by volume or more and 47.0% by volume or less. 、3 It is more preferable that the concentration is 0.0% by volume or more and 7.0% by volume or less. In addition, an inert gas such as nitrogen may be contained as the other gas. In that case, the partial pressure of the inert gas is 、4 It is more preferable that the ratio is 6.0% by volume or more and 64.0% by volume or less. By having these ratios in the above ranges, the pore volume of pores with a diameter of 0.70 nm or less calculated by the QSDFT method from the nitrogen adsorption isotherm per 1 g of the carbonaceous material is 0.16 cm 3 / g or more 0.30cm 3 / g or less, an iodine adsorption amount of 750 mg / g or more and 1,340 mg / g or less, and a reactive black pentavalent amount of 6.0 g / L or more and 67.0 g / L or less can be more easily produced.

[0082] When water vapor gas and oxygen gas are used as the active gas, the flow rate thereof is preferably 10 liters (L) or more and 300 liters (L) or less in total per minute.

[0083] The activation time can be appropriately set depending on the conditions of the raw material, activation temperature, and production equipment. The activation time is, for example, from 10 minutes to 36 hours, preferably from 30 minutes to 24 hours, more preferably from 60 minutes to 12 hours, even more preferably from 100 minutes to 360 minutes, and even more preferably from 120 minutes to 300 minutes. By setting the activation time within the above range, the pore volume of pores with a diameter of 0.70 nm or less calculated by the QSDFT method from the nitrogen adsorption isotherm per 1 g of the carbonaceous material is 0.16 cm 3 / g or more 0.30cm 3 / g or less, an iodine adsorption amount of 750 mg / g or more and 1,340 mg / g or less, and a reactive black pentavalent amount of 6.0 g / L or more and 67.0 g / L or less can be more easily produced.

[0084] The temperature of the activation treatment is not particularly limited, but is preferably 800° C. or higher and 1,250° C. or lower, and more preferably 850° C. or higher and 1,150° C. or lower. By performing the activation treatment at such a temperature, the pore volume of pores with diameters of 0.70 nm or less calculated by the QSDFT method from the nitrogen adsorption isotherm per 1 g of the carbonaceous material is reduced to 0.16 cm. 3 / g or more 0.30cm 3 / g or less, an iodine adsorption amount of 750 mg / g or more and 1,340 mg / g or less, and a reactive black pentavalent amount of 6.0 g / L or more and 67.0 g / L or less can be more easily produced.

[0085] An example of an activation device for performing the activation treatment is a rotary kiln as shown in Figures 1 and 2. Figure 1 is a cross-sectional view I and a side view II of the rotary kiln. Figure 2 is a schematic cross-sectional view for explaining the rotary kiln.

[0086] 1 and 2, a rotary kiln typically includes a tubular body 1 and stirring blades A to F arranged on the inner wall surface of the tubular body 1. An active gas is typically sent from one side to the other, that is, in the case of a rotary kiln as shown in FIGS. 1 and 2, in the direction of flow 2 of the active gas in the tubular body 1.

[0087] The material of the tubular body 1 is not particularly limited as long as it is a material that is used in a rotary kiln, and examples thereof include stainless steel.

[0088] 1 and 2, the number of stirring blades is six, but this can be adjusted appropriately depending on the amount of carbonized material 5 charged as the raw material. The number of stirring blades is usually 1 to 20, preferably 3 to 12, and more preferably 5 to 10. The stirring blades are preferably installed at equal intervals around the central axis of the tubular body 1. For example, if there are six stirring blades, they will be installed at 60° intervals around the central axis of the tubular body 1.

[0089] The height of the stirring blade (height in the direction from the wall of the tubular body 1 toward the center) can be set appropriately depending on the size of the tubular body 1 and the amount of carbonized material 5 charged, but it is preferable that the height is such that the stirring blade is not covered by the carbonized material 5 charged in the tubular body 1 and can be seen. Specifically, when the stirring blade is located at the bottommost surface of the tubular body 1 (the position of stirring blade B in the right diagram of FIG. 2), the height of the stirring blade is preferably such that from 1 / 2 to 2 / 3 of the stirring blade from the bottommost surface is covered by the carbonized material 5. It is more preferable that the height of the stirring blade is 10% to 30% of the inner radius of the tubular body 1.

[0090] The thickness of the stirring blade (thickness in the direction of rotation 3 of the tubular body 1) can be set appropriately depending on the size of the tubular body 1 and the amount of carbonized material 5 charged, but it is preferable that the thickness is such that the stirring blade has a strength sufficient to prevent it from being damaged by the carbonized material 5 charged in the tubular body 1. Specifically, the thickness of the stirring blade is usually 1% or more and 100% or less of the wall thickness of the tubular body 1, preferably 20% or more and 90% or less, and more preferably 30% or more and 95% or less.

[0091] The material of the stirring blade is not particularly limited as long as it is a material that is used in a rotary kiln, and examples thereof include stainless steel.

[0092] By arranging the stirring blades in the tubular body 1 in this manner, the contact efficiency between the carbide 5 and the active gas tends to be improved, which tends to make it easier to produce a carbonaceous material having a desired specific surface area.

[0093] As shown in FIG. 2, an appropriate amount of carbide 5 is charged inside the tube 1. Then, as the tube 1 rotates in the tube rotation direction 3, for example, the carbide 5 collected by the stirring blade A is lifted by the stirring blade A, and then passes over the stirring blade A toward the falling direction 4 of the carbide, where it is mixed, contacted with the active gas and activated, and collected between the stirring blades A and B. As the tube 1 rotates in this manner, the carbide 5 is efficiently and uniformly contacted with the active gas and activated, while being mixed while passing over the stirring blades A to F. This tends to make it easier to produce a carbonaceous material having a desired pore size distribution.

[0094] In this way, by using a rotary kiln as an activation device, the pore volume of pores with diameters of 0.70 nm or less per 1 g of carbonaceous material calculated by the QSDFT method from the nitrogen adsorption isotherm was reduced to 0.16 cm 3 / g or more 0.30cm 3 / g or less, an iodine adsorption amount is 750 mg / g or more and 1,340 mg / g or less, and a reactive black pentavalent amount is 6.0 g / L or more and 67.0 g / L or less.

[0095] By the above activation step, an activated product is obtained.

[0096] The method for producing a carbonaceous material may include a washing step and / or a drying step, etc., in which the activated material is subjected to a washing treatment and / or a drying treatment, etc., after the activation step. The conditions in these steps are not particularly limited, and known conditions can be adopted. In addition, the following washing step and drying step may be referred to.

[0097] (Cleaning process) The carbonaceous material is preferably obtained through a washing step in which the activated product obtained in the activation step is washed. The washing is more preferably performed with an acid. By undergoing such a washing step, the volume of pores with a pore diameter of 0.70 nm or less per gram of the carbonaceous material calculated by the QSDFT method from the nitrogen adsorption isotherm is reduced to 0.16 cm. 3 / g or more 0.30cm 3 / g or less, an iodine adsorption amount of 750 mg / g or more and 1,340 mg / g or less, and a reactive black pentavalent amount of 6.0 g / L or more and 67.0 g / L or less can be more easily produced.

[0098] The types of acids used in the acid washing include, for example, mineral acids such as hydrochloric acid and nitric acid, and organic acids such as formic acid and acetic acid. These acids may be used alone or in combination of two or more.

[0099] The acid concentration, and the temperature and time for acid washing may be appropriately adjusted so as to obtain the desired carbonaceous material.

[0100] (drying process) The carbonaceous material is preferably obtained through a drying step in which the washed product obtained in the washing step is dried.

[0101] The drying method is not particularly limited, and known drying methods such as natural drying, heat drying, and hot air drying can be used. As the drying method, a method of heating and / or reducing pressure is preferable. As the method of drying by heating, a method of drying by hot air is preferable because it is possible to dry stably without unevenness in drying. In terms of drying conditions, it is preferable to dry the carbonaceous material until the moisture content is 20.0 mass % or less, and more preferably until the moisture content is 10.0 mass % or less.

[0102] Examples of the heating method include a heating method using a stationary constant temperature dryer, a stationary hot air dryer, a vacuum dryer, a rotary evaporator, a mixed dryer such as a conical dryer or a Nauter dryer, etc. The heating temperature may be any temperature at which the carbonaceous material hardens but does not melt, and is preferably, for example, 40°C or higher and 300°C or lower.

[0103] The pressure reducing method may be, for example, a pressure reducing method using an oil pump, an oilless pump, an aspirator, etc. The pressure in the pressure reducing method is usually 0.00001 MPa or more and 0.05 MPa or less.

[0104] The drying time depends on the drying temperature, but is usually about 1 minute to 20 hours.

[0105] The carbonaceous material thus obtained may be used as it is, or may be subjected to known methods as necessary, such as crushing, pulverization, and classification to adjust the particle size; additional washing with, for example, water, an organic solvent, an aqueous acid solution, or an aqueous alkali solution to increase the purity; or additional heat treatment to impart durability and adjust the structure, thereby obtaining a carbonaceous material.

[0106] The particle size of the carbonaceous material is preferably adjusted so that its particle size (50% particle size of cumulative distribution on a volume basis, D50) is 20 μm or more and 500 μm or less. By having the particle size of the carbonaceous material in the above range, the carbonaceous material can be suitably used in, for example, the applications exemplified below.

[0107] [Application] The carbonaceous material can be suitably used in various applications for removing, adsorbing, concentrating, and recovering chloroform and anionic surfactants. Such applications may be applications in which the operations of removal, adsorption, concentration, and recovery are appropriately combined. Examples of such applications include adsorption filters, water purifier cartridges, water purifiers, packed towers, water purification equipment including domestic drinking water treatment, water treatment and purification in industrial processes, and wastewater treatment.

[0108] The carbonaceous material is suitable for use in removing chloroform and the like and anionic surfactants and the like.

[0109] [Method for removing chloroform, anionic surfactants, etc.] The method for removing chloroform and the like and the anionic surfactant and the like includes a removal step of removing chloroform and the like and the anionic surfactant and the like using a carbonaceous material. Chloroform and the like and the anionic surfactant and the like are removed, for example, by being adsorbed to the carbonaceous material. The removal method may include steps similar to known methods for removing chloroform and the like and the anionic surfactant and the like, an adsorption method, a concentration method, a recovery method, and the like, in addition to using the carbonaceous material of the present embodiment as the carbonaceous material.

[0110] [Adsorption filter] The adsorption filter of the present embodiment includes the carbonaceous material of the present embodiment. The adsorption filter is preferably used for a water purifier.

[0111] Since the adsorption filter contains a carbonaceous material, it is possible to adsorb a wide range of harmful substances with equal performance, from chloroform, which has a relatively small molecular size, to anionic surfactants, which has a relatively large molecular size. Therefore, for example, by installing the adsorption filter in a water purifier, it is possible to efficiently remove chloroform, anionic surfactants, and the like contained in water.

[0112] The adsorptive filter preferably comprises a carbonaceous material and a fibrous binder.

[0113] Examples of fibrous binders include those that can be shaped by fibrillating the carbonaceous material. Such fibrous binders may be synthetic or natural. Examples of fibrous binders include acrylic fibers, polyethylene fibers, polypropylene fibers, polyacrylonitrile fibers, cellulose fibers, nylon fibers, aramid fibers, and pulp.

[0114] The fibrous binder may be used alone or in combination of two or more. The fibrous binder is preferably polyacrylonitrile fiber and / or pulp. By using these fibrous binders, the density and strength of the adsorption filter can be further increased, and the performance degradation can be suppressed.

[0115] Since the adsorption filter can achieve a higher level of both the removal performance of chloroform, etc. and the anionic surfactant, etc., the adsorption filter contains preferably 20 parts by mass or less, more preferably 10 parts by mass or less, of the fibrous binder per 100 parts by mass of the carbonaceous material. The lower limit is usually 0.01 parts by mass or more. In addition, when the adsorption filter contains other functional components described below, "per 100 parts by mass of the carbonaceous material" in the filter composition should be read as "per 100 parts by mass of the carbonaceous material and other functional components combined."

[0116] The adsorption filter may contain other functional components as long as the effect of the present embodiment is not impaired. Examples of such other functional components include lead adsorbents such as titanosilicate and zeolite powders that can adsorb and remove soluble lead, ion exchange resins, chelating resins, and various adsorbents containing silver ions and / or silver compounds to impart antibacterial properties.

[0117] When passing water through an adsorption filter, the water is usually passed at a space velocity (SV) of 300 / hr to 6500 / hr to avoid excessive pressure loss. The performance of an adsorption filter can be confirmed by plotting the relationship between each removal rate calculated from the concentration of the target substance in the raw water and permeated water and the ratio of the amount of water (L) passed from the start of water flow to the volume of the water purification cartridge (mL) (cumulative permeated water volume L / mL).

[0118] (filtration capacity) In this specification, the filtration capacity is defined as the amount of water (L) that can be passed through an adsorption filter until the removal rate of the target substance reaches 80%. The water is passed through the adsorption filter at a space velocity (SV) of 3000 / hr.

[0119] (Chloroform filtration capacity) Chloroform filtration capacity can be measured with reference to the volatile organic compound removal performance test in the test method specified in the "Household Water Purifier Test Method" in JIS S3201:2019. Specifically, the test water has a chloroform concentration of 0.060±0.012 (mg / L) and a water temperature of 20°C±3°C, and is passed through a carbonaceous material or an adsorption filter. The test raw water and the filtrate are analyzed by headspace gas chromatography, and the removal rate (%) is calculated from the test raw water concentration (mg / L) and the filtrate concentration (mg / L). The removal rate (%) is plotted against the cumulative water flow rate (L) to determine the filtration capacity.

[0120] The adsorption filter of the present embodiment has excellent filtering ability, and the filtering ability of chloroform measured in accordance with JIS S3201:2019 is usually 1 cm of carbonaceous material. 3 The capacity is 5.0 L or more, preferably 6.5 L or more, and more preferably 8.0 L or more.

[0121] (Anionic surfactant filtration capacity) The anionic surfactant filtration capacity can be measured using the anionic surfactant removal performance test in the test method specified in the "Household Water Purifier Test Method" in JIS S3201:2019. Specifically, the test water is set to an anionic surfactant concentration of 0.20±0.04 (mg / L) and a water temperature of 20°C±3°C, and passed through a carbonaceous material or an adsorption filter. The test raw water and the filtrate are analyzed by solid phase extraction-high performance liquid chromatography, and the removal rate (%) is calculated from the test raw water concentration (mg / L) and the filtrate concentration (mg / L). The removal rate (%) is plotted against the cumulative water flow rate (L) to determine the filtration capacity.

[0122] The adsorption filter of the present embodiment has excellent filtering ability, and therefore the filtering ability of the adsorption filter is usually 1 cm of carbonaceous material, as measured in accordance with JIS S3201:2019. 3 The capacity is 5.0 L or more, preferably 8.0 L or more, and more preferably 10.0 L or more.

[0123] [Water purifier cartridge] The water purifier cartridge of this embodiment includes the carbonaceous material of this embodiment. The water purifier cartridge may have the same configuration as a known water purifier cartridge, except for including the carbonaceous material of this embodiment. The water purifier cartridge can efficiently remove chloroform and the like and anionic surfactants and the like contained in water by including a carbonaceous material. Therefore, for example, by installing the water purifier cartridge in a household water purifier, it is possible to efficiently remove many types of harmful substances, particularly chloroform and the like and anionic surfactants, described in the "Household Water Purifier Test Method" in JIS S3201:2019.

[0124] Examples of the water purification cartridge include a cartridge in which a housing is filled with a carbonaceous material and a cartridge in which a housing is filled with an adsorption filter. The water purification cartridge may include a combination of a known nonwoven fabric filter, various adsorption materials, mineral additives, ceramic filtering materials, and hollow fiber membranes in addition to the carbonaceous material or adsorption filter according to the present embodiment.

[0125] [Device] The device includes a carbonaceous material. The device may have the same configuration as a known device, except that the carbonaceous material of the present embodiment is used as the carbonaceous material.

[0126] The function of the carbonaceous material is utilized by an apparatus containing the carbonaceous material. The apparatus is preferably a treatment apparatus. In this specification, the term "treatment apparatus" is not particularly limited as long as it is an apparatus that can remove, adsorb, concentrate, and recover chloroform and the like and anionic surfactants and the like contained in the treatment target such as wastewater, waste liquid, and oil by the carbonaceous material of this embodiment. Such a treatment apparatus may be an apparatus that appropriately combines the operations of removal, adsorption, concentration, and recovery. Examples of such treatment apparatus include apparatuses containing adsorption filters, columns, tanks or baths, tubes, water purifier cartridges, cylinders, and sheets (hereinafter also simply referred to as "filters, etc. containing carbonaceous materials"), packed towers, and filtration apparatuses such as water purifiers, adsorption measures, and concentration apparatuses. Examples of such apparatuses include household drinking water treatment apparatuses, water treatment and purification apparatuses in industrial processes, and wastewater treatment apparatuses.

[0127] The device includes an adsorption section for contacting the carbonaceous material with, for example, chloroform or the like and an anionic surfactant. The adsorption section may contain an adsorbent other than the carbonaceous material according to the present embodiment, as necessary. Examples of such adsorbents include activated carbon, zeolite, silica gel, activated alumina, nonwoven fabric, and porous organic compounds other than the carbonaceous material according to the present embodiment.

[0128] Filtration devices include, for example, water purifiers, cartridge-type filtration devices, membrane treatment devices, and ultrafiltration membrane devices that include carbonaceous materials.

[0129] The treatment device may be equipped with other adsorption filters in addition to the adsorption filter containing a carbonaceous material, etc. Examples of such other adsorption filters include metal filters made of stainless steel, aluminum, bronze, copper, titanium, nickel, etc.; and resin filters made of polypropylene, polyvinyl chloride, polyvinylidene chloride, polyethylene, polyamide, fluorine-based resin, etc.

[0130] Additionally, the processing equipment may be of a batch or continuous type, and the carbonaceous material may be used in either mode.

[0131] [Water purifier] The water purifier of the present embodiment includes the carbonaceous material of the present embodiment.

[0132] The water purifier is manufactured using a carbonaceous material or an adsorption filter. By including an adsorption filter, the water purifier can remove a wide range of harmful substances, from chloroform having a relatively small molecular size to anionic surfactants having a relatively large molecular size, with the same performance. Therefore, the water purifier can be suitably used for faucets and kitchens.

[0133] The water purifier includes a water purification cartridge, and the water purification cartridge is preferably configured using the carbonaceous material or the adsorption filter according to the present embodiment. For example, the configuration of such a water purification cartridge may refer to the above-mentioned water purifier cartridge.

[0134] (Water purification method) The water purification method is not particularly limited, but it is preferable to use the water purifier of the present embodiment. The water purification method is not particularly limited, and a known method can be used.

[0135] [Water purification equipment] The water purification equipment of the present embodiment includes the carbonaceous material of the present embodiment. By including the carbonaceous material, the water purification equipment can achieve high levels of both free residual chlorine and anionic surfactant removal performance.

[0136] Examples of water purification equipment include pure water production equipment, ultrapure water equipment, water purification equipment such as water purification plants, general industrial wastewater treatment equipment, and water purification equipment for pharmaceuticals and food. EXAMPLES

[0137] EXAMPLES The present invention will be explained in more detail below by showing examples and comparative examples, but the present invention is not limited to these examples in any way.

[0138] [Evaluation method]

[0139] (1) Pore volume with a pore diameter of 0.70 nm or less Measurement of nitrogen gas adsorption isotherm using BELSORP-MAX Using a specific surface area / pore distribution measuring device (BELSORP (registered trademark)-MAX (product name) manufactured by Microtrack-Bel Co., Ltd.), the carbonaceous material was heated at 300°C for 3 hours under vacuum conditions, and then the nitrogen gas adsorption isotherm was measured at a temperature of 77K.

[0140] Pore ​​volume measurement The pore volume (cm) of micropores with a pore diameter of 0.70 nm or less calculated by the QSDFT method per 1 g of carbonaceous material from the nitrogen adsorption isotherm 3 / g) was calculated as follows. Specifically, the nitrogen gas adsorption isotherm value obtained by the above "Measurement of nitrogen gas adsorption isotherm using BELSORP-MAX" was used, and the pore size distribution was calculated by applying N2at 77K carbon[slit pore / cyl.pore (QSDFT Ads.model)] as a calculation model, to obtain the pore volume (cm) of pores with a diameter of 0.70 nm or less. 3 / g) was calculated.

[0141] (2) Iodine adsorption capacity (iodine adsorption performance) The iodine adsorption amount (mg / g) of the carbonaceous material was measured and calculated. Specifically, the measurement of the iodine adsorption amount was performed in accordance with JIS K1474 (2014). That is, first, in accordance with JIS Z8801-1, the carbonaceous material was pulverized until 90% or more passed through a 45 μm mesh sieve, and then dried in a constant temperature dryer (DVS402 (product name) manufactured by Yamato Scientific Co., Ltd.) at 115° C. for 3 hours. Thereafter, the material was allowed to cool to room temperature in a desiccator using silica gel as a desiccant, and a carbonaceous material after cooling was obtained.

[0142] Meanwhile, 25.0 g of potassium iodide (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) and 13.0 g of iodine (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) were dissolved in approximately 1 L of distilled water to prepare an iodine solution. The iodine solution was titrated with a 0.1 mol / L sodium thiosulfate solution (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.), and distilled water was appropriately added to the iodine solution to prepare a 0.05 mol / L iodine solution.

[0143] Next, an arbitrary amount of the carbonaceous material after cooling (an amount such that the residual iodine concentration in the supernatant of the filtrate below is approximately 2.5 g / L) was weighed and placed in a 100 mL Erlenmeyer flask with a stopper, and 50 mL of the 0.05 mol / L iodine solution was added to the entire amount using a pipette. At room temperature (20°C to 30°C), the mixture was shaken at 200 times / min for 15 minutes using a shaker (medium-sized shaker Reciprocating Shaker NR-10 (trade name) manufactured by Taitec Co., Ltd.) to adsorb iodine to the carbonaceous material, thereby obtaining a mixed liquid. Thereafter, the mixed liquid was filtered using a cellulose mixed ester membrane filter (A045A025A (trade name) manufactured by Advantec Toyo Co., Ltd.) to obtain a filtrate. 10 mL of the supernatant of the filtrate was collected using a pipette and titrated with 0.1 mol / L sodium thiosulfate solution (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., factor: 1.000), and the residual iodine concentration was calculated using the following formula (I). Residual iodine concentration (g / L) = amount of 0.1 mol / L sodium thiosulfate solution used in titration (mL) × factor of 0.1 mol / L sodium thiosulfate solution × 12.69 / 10 (I)

[0144] The amount of iodine adsorption per 1 g of the carbonaceous material was calculated by the following formula (II). Amount of iodine adsorbed per 1 g of carbonaceous material = (10 × factor of 0.05 mol / L iodine solution – amount of 0.1 mol / L sodium thiosulfate solution used in titration (mL) × factor of 0.1 mol / L sodium thiosulfate solution) × 12.69 × 5 / mass of carbonaceous material (g) (II)

[0145] The factor of the 0.05 mol / L iodine solution was calculated using formula (III). Factor of 0.05 mol / L iodine solution = (amount of 0.1 mol / L sodium thiosulfate solution used in titration (mL) × factor of 0.1 mol / L sodium thiosulfate solution) / 10 (III)

[0146] Using Freundlich's adsorption isotherm, an adsorption isotherm was created with the horizontal axis representing the residual iodine concentration and the vertical axis representing the amount of iodine adsorbed per 1 g of carbonaceous material, and the amount of iodine adsorbed (mg / g) per 1 g of carbonaceous material at a residual iodine concentration of 2.5 g / L was calculated. The amount of iodine adsorbed was taken as the iodine adsorption performance.

[0147] (3) Reactive Black Pentavalent The reactive black pentavalent (g / L) of the carbonaceous material was measured. Specifically, the carbonaceous material was first crushed to a volume-based cumulative distribution 50% particle size (D50) of about 10.0 μm or less, and then dried in a constant temperature dryer (Yamato Scientific Co., Ltd. DVS402 (product name)) at 115° C. for 3 hours. Thereafter, the material was allowed to cool to room temperature in a desiccator using silica gel as a desiccant, and a carbonaceous material was obtained after cooling.

[0148] Meanwhile, test solution A containing phosphate buffer and Reactive Black 5 (Sigma-Aldrich) was prepared as follows. That is, first, 7.26 g of potassium dihydrogen phosphate (Fuji Film Wako Pure Chemical Industries, Ltd.) and 28.66 g of disodium hydrogen phosphate 12-hydrate (Fuji Film Wako Pure Chemical Industries, Ltd.) were dissolved in 2 L of distilled water to prepare a phosphate buffer (pH: 7.0). Then, Reactive Black 5 was added to 1 L of the obtained phosphate buffer in an amount of about 0.5 g to 1.2 g to prepare test solution A. The amount of Reactive Black 5 was adjusted as follows. That is, the amount of Reactive Black 5 added to 1 L of phosphate buffer was appropriately adjusted so that the absorbance of the solution obtained by diluting the obtained test solution A 20 times with distilled water was in the range of 1.18 to 1.23. The absorbance was measured at a wavelength of 594 nm using a glass cell with an optical path length of 10 mm with an ultraviolet-visible spectrophotometer (double beam spectrophotometer U-2910 (product name) manufactured by Hitachi High-Tech Corp.) The test solution A obtained as described above was diluted 20 times to prepare test solution B, which was used in the absorbance measurement described below.

[0149] Next, an arbitrary mass (an amount in which the residual rate of Reactive Black 5 contained in the filtrate according to the following formula (V) is about 10%) of the carbonaceous material after cooling was taken into a 100 mL Erlenmeyer flask with a stopper, and the carbonaceous material was added to 50 mL of the test liquid A prepared above, and the mixture was shaken at a speed of 150 times / min for 5 hours in a water bath at 40°C using a constant temperature shaking bath (Water Bath Shaker MM-10 (trade name) manufactured by Taitec Co., Ltd.) to obtain a mixed liquid. Thereafter, the mixed liquid was filtered using a membrane filter (DISMIC (registered trademark) 25HP045AN (trade name) manufactured by Advantec Toyo Co., Ltd.) to obtain a filtrate.

[0150] The absorbance at a wavelength of 594 nm of each of the obtained test liquid B and the filtrate was measured using a glass cell with an optical path length of 10 mm and an ultraviolet-visible spectrophotometer (double beam spectrophotometer U-2910 (product name) manufactured by Hitachi High-Tech Corporation). Using these absorbances, the adsorption amount of Reactive Black 5 per 1 g of carbonaceous material (hereinafter simply referred to as "RB5 adsorption amount ( / g) per 1 g of carbonaceous material") was calculated using the following formula (IV). Amount of RB5 adsorbed per 1 g of carbonaceous material ( / g) = (absorbance of test solution B at 594 nm × 20 – absorbance of filtrate at 594 nm) / mass of carbonaceous material (g) (IV)

[0151] Furthermore, the residual rate of Reactive Black 5 contained in the filtrate (hereinafter simply referred to as "RB5 residual rate (%)") was calculated by the following formula (V). RB5 remaining rate (%) = (absorbance of filtrate at 594 nm / absorbance of test solution B at 594 nm × 20) × 100 (V)

[0152] Next, a power approximation curve was created using the RB5 residual rate (%) on the horizontal axis and the RB5 adsorption amount ( / g) per 1 g of carbonaceous material on the vertical axis. Using this power approximation formula, the adsorption amount of Reactive Black 5 when the Reactive Black 5 residual rate was 1% (hereinafter simply referred to as "RB5 adsorption amount ( / g) when the RB5 residual rate was 1%) was obtained, and the Reactive Black 5 value (g / L) was calculated using formula (VI). Reactive Black 5 value (g / L) = (absorbance of test solution B at 594 nm × 20 × 0.99 / absorbed amount of RB5 at 1% residual rate ( / g)) / 0.05 (L) (VI) In addition, 0.05 (L) in formula (VI) is the volume of the test liquid.

[0153] (4) Mesopore ratio Measurement of pore volume with a pore diameter of 1.00 nm or less The pore volume (cm) of micropores with a pore diameter of 1.00 nm or less calculated by the QSDFT method per 1 g of carbonaceous material from the nitrogen adsorption isotherm 3 / g) was calculated as follows. Specifically, the nitrogen gas adsorption isotherm value obtained by "Measurement of nitrogen gas adsorption isotherm using BELSORP-MAX" for the pore volume with a pore diameter of 0.70 nm or less was used, and the pore size distribution was calculated by applying N2at 77K carbon[slit pore / cyl.pore (QSDFT Ads.model)] as a calculation model, to obtain the pore volume (cm) with a pore diameter of 1.00 nm or less. 3 / g) was calculated.

[0154] Mesopore volume measurement The mesopore volume (cm) of carbonaceous materials determined by the BJH method from the N2 adsorption isotherm at -196°C. 3 / g) was measured. Specifically, the nitrogen adsorption isotherm used in the measurement of the BET specific surface area described below was used to obtain a curve by BJH analysis in the relative pressure region P / P0 = 0.385 to 0.99. From the obtained curve, the cumulative pore volume for each pore size was calculated, and the pore volume of mesopores with pore sizes of 2.0 nm to 50.0 nm was calculated by subtracting the cumulative pore volume for pore sizes up to 2.0 nm from the cumulative pore volume for pore sizes up to 50.0 nm.

[0155] Calculation of mesopore ratio The mesopore ratio of the carbonaceous material was calculated. Specifically, the mesopore ratio (A / B) of a carbonaceous material is the ratio of the pore volume (cm) of pores with a diameter of 1.00 nm or less. 3 / g) (A) and mesopore volume (cm 3 / g) (B) was used to calculate according to the following formula (VII). Mesopore ratio of carbonaceous material (A / B) = pore volume of pores with diameters of 1.00 nm or less (A) / mesopore volume (B) (VII)

[0156] (5) Mesopore volume The mesopore volume (cm) of carbonaceous materials determined by the BJH method from the N2 adsorption isotherm at -196°C. 3 / g) was measured and calculated by the "measurement of mesopore volume" in the above mesopore ratio.

[0157] (6) BET specific surface area The specific surface area (m2) of carbonaceous materials determined by the BET method from the N2 adsorption isotherm at -196℃ 2 / g) was measured. Specifically, the BET specific surface area (m 2 The specific surface area (P / g) was determined as follows. That is, first, a specific surface area / pore distribution measuring device (BELSORP (registered trademark)-miniII (product name) manufactured by Microtrack-Bell Corporation) was used to heat the carbonaceous material at 250°C for 3 hours under reduced pressure (vacuum degree: 0.1 kPa or less), and then the nitrogen adsorption isotherm of the carbonaceous material at -196°C was measured. Using the obtained nitrogen adsorption isotherm, a straight line was obtained from the obtained curve by BET analysis in the region of relative pressure P / P0 = 0.01 or more and 0.10 or less by the multipoint method, and the BET specific surface area was calculated from this straight line.

[0158] (7) Packing density The packing density (g / mL) of the carbonaceous material was calculated as measured by the tapping method. Specifically, the carbonaceous material was first dried for 3 hours in a constant temperature dryer (DVS402 (product name) manufactured by Yamato Scientific Co., Ltd.) at 115° C. Thereafter, it was allowed to cool to room temperature in a desiccator using silica gel as a desiccant, and a carbonaceous material was obtained after being allowed to cool.

[0159] 5.0 g of the carbonaceous material after cooling was weighed and divided into roughly three equal parts, and a part of the carbonaceous material (about 1 / 3 of the amount) was placed in a 150 mL measuring cylinder (inner diameter: 31 mm, (Tsutsui Rikagaku Kikai Co., Ltd.). The measuring cylinder was fitted with a rubber stopper and set in an automatic tapping device (Tsutsui Rikagaku Kikai Co., Ltd., powder reduction degree measuring instrument TPM-3A type (product name)), and tapping was performed for 1 minute with a shaking width of 45 mm and a shaking frequency of 35 to 36 times per minute. After the tapping was completed, another part (about 1 / 3 of the amount) of the carbonaceous material previously divided into three equal parts was further added to the measuring cylinder, a rubber stopper was attached, and tapping was performed for 1 minute under the same conditions as above. Thereafter, the last part (about 1 / 3 of the amount) of the carbonaceous material previously divided into three equal parts was further added to the measuring cylinder, a rubber stopper was attached, and tapping was performed for 30 minutes under the same conditions as above.

[0160] After the tapping was completed, the rubber stopper was removed, the top surface of the sample in the measuring cylinder was flattened with a spatula or the like, and the sample volume (mL) was visually measured from the graduations on the measuring cylinder. Using the measured sample volume, the packing density measured by the tapping method was calculated according to the following formula (VIII). Packing density (g / mL) = mass of carbonaceous material (g) / measured sample volume (mL) (VIII)

[0161] (8) Chloroform filtration capacity The chloroform filtration capacity (L / cm) of carbonaceous materials was measured under the chloroform filtration capacity test conditions specified in the "Testing method for household water purifiers" in JIS S3201:2019. 3 ) was calculated. The filtration capacity test was carried out by placing 50 cm of carbonaceous material in a descending water column made of Duracon (registered trademark) (polyacetal) (machined product designed by the company, with an inner diameter of φ50 mm and a height of 60 mm). 3 The filtration was carried out at a flow rate of 3.0 L / min.

[0162] (9) Anionic surfactant filtration capacity The anionic surfactant filtration capacity (L / cm2) of carbonaceous materials under the anionic surfactant filtration capacity test conditions specified in the "Test method for household water purifiers" in JIS S3201:2019 3 ) was calculated. The filtration capacity test was carried out by placing 50 cm of carbonaceous material in a descending water column made of Duracon (registered trademark) (polyacetal) (machined product designed by the company, with an inner diameter of φ50 mm and a height of 60 mm). 3 The filtration was carried out at a flow rate of 3.0 L / min.

[0163] Example 1 (carbonization process) A charcoal was obtained by carbonizing coconut shells from the Philippines at a temperature of 600°C for approximately 2 hours.

[0164] (Activation treatment) The obtained charcoal was placed in a rotary kiln with stirring blades installed in the furnace heated to 900°C, as shown in Figs. 1 and 2, with a volume of 1 m 3 The amount of the powder was about 0.06 times the amount of the powder. Then, while rotating the kiln at a rotation speed of 3.0 rpm, gas (40.0% steam by volume, 5.0% oxygen by volume, and 55.0% nitrogen by volume) was introduced into the kiln, and activation treatment was performed for 130 minutes to obtain an activated material.

[0165] In the rotary kiln used, six stirring blades were installed at 60° intervals around the central axis of the tube. The height of the stirring blades was 15% to 25% of the inner radius of the tube, and the thickness of the stirring blades was 40% to 80% of the thickness of the tube.

[0166] (Cleaning process, drying process, etc.) The obtained activated material was washed with dilute hydrochloric acid, then thoroughly washed with water to remove residual hydrochloric acid, and dried to obtain a dried material. The obtained dried material was then pulverized and sieved using a standard sieve wire mesh specified in JIS Z8801-1:2019, with a 140 mesh sieve (mesh size: 106 μm, Tokyo Screen Co., Ltd.) and a 60 mesh sieve (mesh size: 233 μm, Tokyo Screen Co., Ltd.) to adjust the particle size (50% particle size of cumulative distribution on a volume basis, D50) to 210 μm, thereby obtaining pulverized carbonaceous material 1, which is activated carbon.

[0167] Example 2 A pulverized carbonaceous material 2, which is activated carbon, was obtained in the same manner as in Example 1, except that the activation treatment was carried out for 200 minutes in the activation step.

[0168] Example 3 A pulverized carbonaceous material 3, which is activated carbon, was obtained in the same manner as in Example 1, except that the activation treatment was carried out for 250 minutes in the activation step.

[0169] Example 4 A pulverized carbonaceous material 4, which is activated carbon, was obtained in the same manner as in Example 1, except that the activation treatment was carried out for 280 minutes in the activation step.

[0170] Comparative Example 1 (carbonization process) A charcoal was obtained by carbonizing coconut shells from the Philippines at a temperature of 600°C for approximately 2 hours.

[0171] (Activation treatment) The obtained charcoal was placed in a rotary kiln with stirring blades installed in the furnace heated to 900°C, as shown in Figs. 1 and 2, with a volume of 1 m 3 The amount of the powder was about 0.06 times the amount of the powder. Then, while rotating the kiln at a rotation speed of 3.0 rpm, gas (water vapor 40.0% by volume, oxygen 5.0% by volume, and nitrogen 55.0% by volume) was introduced into the kiln, and activation treatment was performed for 1 minute to obtain an activated material.

[0172] (Cleaning process, drying process, etc.) The obtained activated material was washed with dilute hydrochloric acid, then thoroughly washed with water to remove residual hydrochloric acid, and dried to obtain a dried material. The obtained dried material was then pulverized and sieved through a standard sieve mesh specified in JIS Z8801-1:2019 using a 140 mesh sieve (mesh size: 106 μm, Nishimura Wire Mesh Mfg. Co., Ltd.) and a 60 mesh sieve (mesh size: 233 μm, Nishimura Wire Mesh Mfg. Co., Ltd.) to adjust the particle size (50% particle size of cumulative distribution on a volume basis, D50) to 210 μm, thereby obtaining pulverized carbonaceous material 5, which is activated carbon.

[0173] Comparative Example 2 In the activation step, gas (water vapor 30.0% by volume, oxygen 2.5% by volume, and nitrogen 67.5% by volume) was introduced into the kiln, and activation treatment was carried out for 260 minutes. In the same manner as in Example 1, however, pulverized carbonaceous material 6, which is activated carbon, was obtained.

[0174] Comparative Example 3 In the activation step, gas (water vapor 30.0% by volume, oxygen 2.5% by volume, and nitrogen 67.5% by volume) was introduced into the kiln, and activation treatment was carried out for 390 minutes. In the same manner as in Example 1, however, pulverized carbonaceous material 7, which is activated carbon, was obtained.

[0175] [Table 1] [Industrial Applicability]

[0176] The carbonaceous material of the present embodiment can be suitably used for various applications for removing, adsorbing, concentrating, and recovering a wide range of hazardous substances, from chloroform, which has a relatively small molecular size, to anionic surfactants, which has a relatively large molecular size, with equivalent performance. [Explanation of symbols]

[0177] A, B, C, D, E, F... stirring blade, 1... tube body, 2... flow direction of active gas, 3... rotation direction of tube body, 4... falling direction of carbonized material, 5... carbonized material.

Claims

1. The pore volume of pores with diameters of 0.70 nm or less per 1 g of carbonaceous material calculated by the QSDFT method from the nitrogen adsorption isotherm is 0.16 cm 3 / g or more 0.30cm 3 / g or less, The iodine adsorption amount is 750 mg / g or more and 1,340 mg / g or less, Reactive Black pentavalent is 6.0 g / L or more and 30.0 g / L or less; The specific surface area, as determined by the BET method from the N 2 adsorption isotherm at −196° C., is 610 m 2 / g or more and 1,400 m 2 / g or less. carbonaceous material.

2. The pore volume (A) of pores with a diameter of 1.00 nm or less calculated by the QSDFT method per 1 g of carbonaceous material from the nitrogen adsorption isotherm and the N 2 2. The carbonaceous material according to claim 1, wherein a ratio (A / B) of the pore volume (B) of the mesopores obtained from the adsorption isotherm of (A) to the pore volume (B) of the mesopores is 3.0 or more and 8.0 or less.

3. N at -196°C 2 The mesopore volume calculated by the BJH method from the adsorption isotherm is 0.030 cm 3 / g or more 0.140cm 3 / g or less.

4. 2. The carbonaceous material according to claim 1, having a packing density measured by a tapping method of 0.36 g / mL or more and 0.60 g / mL or less.

5. The carbonaceous material according to any one of claims 1 to 4, which is used for removing at least chloroform and an anionic surfactant in water.

6. a carbonization step of carbonizing the raw material to obtain a carbonized material; The method for producing a carbonaceous material according to any one of claims 1 to 4, further comprising: an activation step of subjecting the carbide to an activation treatment to obtain an activated product.

7. The method according to claim 6 , further comprising a washing step of washing the activated material.

8. The method according to claim 6, wherein the raw material is coconut shell.

9. An adsorption filter comprising the carbonaceous material according to any one of claims 1 to 4.

10. A water purifier cartridge comprising the carbonaceous material according to any one of claims 1 to 4.

11. A water purifier comprising the carbonaceous material according to any one of claims 1 to 4.

12. A water purification facility comprising the carbonaceous material according to any one of claims 1 to 4.

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