Filters

Abstract

The main object of the present invention is to provide a filter that has excellent performance in removing fluorine-containing organic compounds even when the superficial velocity (SV) of the water to be treated is high. The filter of the present invention includes an activated carbon molded body, and the activated carbon molded body has a pore volume A (cc / g) of pores with a pore diameter of 2.0 nm or less of 0.30 cc / g or more and a pore volume B (cc / g) of pores with a pore diameter in the range of 3.0 to 3.5 nm of 0.01 cc / g or more, among the pore volumes calculated by the QSDFT method.

Description

[Technical field]

[0001] The present invention relates to a filter including, as a constituent member, an activated carbon molded body containing activated carbon. [Background technology]

[0002] In recent years, there has been growing concern about the safety and health of tap water quality, and it is desirable to remove various harmful substances. In terms of water quality management, perfluoroalkylsulfonic acids, such as perfluorooctane sulfonic acid (PFOS), and perfluoroalkylcarboxylic acids, such as perfluorooctanoic acid (PFOA), are particularly notable as substances that are of concern for their adverse health effects. Efforts to remove these substances from drinking water, etc., to reduce health and environmental risks have begun worldwide. In Japan, from the perspective of appropriate water quality management at water purification plants, a target value (provisional) of 50 ng / L for PFOS and PFOA in total was set from April 1, 2020, and the status of PFOS and PFOA was changed from "item requiring consideration" to "item for setting water quality management targets" (Notification of the Director-General for Food Safety and Environmental Health, Minister's Secretariat, Ministry of Health, Labour and Welfare, dated March 30, 2020, No. 0330-1, "Regarding Partial Amendments to the Ministerial Ordinance on Water Quality Standards (Enforcement Notification)").

[0003] To date, a technique using a filter containing activated carbon has been proposed as a technique for removing fluorine-containing organic compounds (perfluoroalkyl compounds and polyfluoroalkyl compounds, hereinafter also referred to as "PFAS") from water to be treated (water to be treated). For example, Patent Document 1 discloses a filter having a benzene adsorption amount of 30 to 60%, a vitamin B12 adsorption amount of more than 50.0 mg / g, and a mesopore volume of 0.13 to 0.30 cm3 calculated from a nitrogen adsorption isotherm by the BJH method. 3 The paper discloses a fluorine-containing organic compound removal material made of a carbonaceous material with a fluorine content of 1000 ppm / g. The paper also describes that the removal material has high PFAS (PFOS, PFOA, etc.) removal performance and can be used in water purifier applications. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2022 / 085550 Summary of the Invention [Problem to be solved by the invention]

[0005] Patent Document 1 describes a carbonaceous material in which the pore volume of mesopores (pores with a pore diameter in the range of 2 to 50 nm) is 0.130 to 0.30 cm 3 / g, which makes the carbonaceous material more suitable for adsorbing PFAS. However, the inventors' investigations revealed that when the superficial velocity (SV) of the water to be treated is high during filtration (for example, when the SV is 2500 h -1 The inventors have found that in cases where the pore volume of the mesopores is within the above range, the removal performance of the fluorine-containing organic compounds may not be sufficient.

[0006] Therefore, a main object of the present invention is to solve the above problems and to provide a filter that has excellent performance for removing fluorine-containing organic compounds even when the superficial velocity (SV) of the water to be treated is high. [Means for solving the problem]

[0007] The present inventors have investigated the above problem. One document states that the molecular size of PFAS is 2 nm or less. From this, it may be thought that it would be effective to increase the volume of pores with a pore diameter of 1.0 nm or less. However, as a result of the inventors' repeated investigations, it was found that when the superficial velocity (SV) of the water to be treated is high (for example, when the SV is 2500 h -1In the case of a filter having a pore volume of pores with a pore diameter of 2 nm or less that is a specific value or more, it is important that the mesopores include pores in a specific pore diameter range, i.e., pores with a pore diameter of 3.0 to 3.5 nm, and it is important to control the pore volume of pores with a pore diameter of 3.0 to 3.5 nm to be a specific value or more. The present invention is an invention that was completed based on these findings and through further investigations.

[0008] That is, the present invention provides the following aspects. Item 1. A filter comprising an activated carbon molded body containing activated carbon, wherein the activated carbon molded body has a pore volume calculated by a QSDFT method in which a pore volume A (cc / g) of pores having a pore diameter of 2.0 nm or less is 0.30 cc / g or more, and a pore volume B (cc / g) of pores having a pore diameter in the range of 3.0 to 3.5 nm is 0.01 cc / g or more. Item 2. The filter according to item 1, wherein the pore volume of the activated carbon molded body calculated by the QSDFT method for pores with a pore size of 0.65 nm or less is 0.015 cc / g or more and 0.08 cc / g or less. Item 3. The filter according to item 1 or 2, wherein the pore volume of the activated carbon molded body calculated by the QSDFT method for pores having a pore diameter of 1.0 nm or less is 0.15 cc / g or more and 0.35 cc / g or less. Item 4. The filter according to any one of Items 1 to 3, wherein the pore volume of the activated carbon molded body, calculated by a QSDFT method, of pores having a pore diameter of 1.5 nm or less is 0.25 cc / g or more and 0.5 cc / g or less. Item 5. The filter according to any one of Items 1 to 4, wherein the activated carbon molded body has a pore volume C of pores having a pore diameter of 2.0 nm or more, calculated by a QSDFT method, of 0.05 cc / g or more and 0.8 cc / g or less. Item 6. The filter according to any one of Items 1 to 5, wherein the pore volume of the activated carbon molded body calculated by a QSDFT method has a pore volume of pores having a pore diameter in the range of 0.65 to 0.8 nm of 0.05 cc / g or more and 0.1 cc / g or less. Item 7. The filter according to any one of Items 1 to 6, wherein the activated carbon molded body has a pore volume of pores having a diameter in the range of 0.8 to 1.0 nm, the pore volume being calculated by a QSDFT method, of 0.05 cc / g or more and 0.25 cc / g or less. Item 8. The filter according to any one of Items 1 to 7, wherein the activated carbon molded body has a pore volume of pores having a diameter in the range of 1.0 to 1.5 nm, the pore volume being calculated by a QSDFT method, of 0.08 cc / g or more and 0.20 cc / g or less. Item 9. The filter according to any one of Items 1 to 8, wherein the pore volume of the activated carbon molded body calculated by a QSDFT method has a pore volume of pores having a pore diameter in the range of 1.3 to 1.5 nm of 0.001 cc / g or more and 0.08 cc / g or less. Item 10. The filter according to any one of Items 1 to 9, wherein the pore volume of the activated carbon molded body calculated by a QSDFT method has a pore volume of pores having a pore diameter in the range of 1.5 to 2.0 nm of 0.001 cc / g or more and 0.10 cc / g or less. Item 11. The filter according to any one of Items 1 to 10, wherein the activated carbon molded body has a pore volume of pores having diameters in the range of 2.0 to 2.5 nm, the pore volume being calculated by a QSDFT method, of 0.1 cc / g or less. Item 12. The filter according to any one of Items 1 to 11, wherein the activated carbon molded body has a pore volume of pores having diameters in the range of 2.5 to 3.0 nm of 0.15 cc / g or less, as calculated by a QSDFT method. Item 13. The filter according to any one of Items 1 to 12, wherein the activated carbon molded body has a pore volume of pores having diameters in the range of 3.5 to 4.0 nm of 0.1 cc / g or less, as calculated by a QSDFT method. Item 14. The filter according to any one of Items 1 to 13, wherein the activated carbon molded body has a pore volume of pores having a pore diameter in the range of 3.0 to 4.0 nm, the pore volume being calculated by a QSDFT method, of 0.01 cc / g or more and 0.35 cc / g or less. Item 15. The filter according to any one of Items 1 to 14, wherein the activated carbon molded body has a pore volume of pores having diameters in the range of 4.0 to 4.5 nm, calculated by a QSDFT method, of 0.1 cc / g or less. Item 16. The filter according to any one of Items 1 to 15, wherein the pore volume of the activated carbon molded body, calculated by a QSDFT method, for pores with diameters of 4.0 nm or more is 0.05 cc / g or more and 0.13 cc / g or less. Item 17. The filter according to any one of Items 1 to 16, wherein the activated carbon molded body has a total pore volume T calculated by a QSDFT method of 0.4 cc / g or more and 1.2 cc / g or less. Item 18. The filter according to any one of Items 1 to 17, wherein the activated carbon molded body has a ratio (A / T) of a pore volume A (cc / g) having a pore diameter of 2.0 nm or less in the pore volume calculated by the QSDFT method to a total pore volume T (cc / g) calculated by the QSDFT method of 0.3 to 0.9. Item 19. The filter according to any one of Items 1 to 18, wherein the activated carbon molded body has a ratio (B / T) of a pore volume B (cc / g) of pores having a pore diameter in the range of 3.0 to 3.5 nm, calculated by the QSDFT method, to a total pore volume T (cc / g) calculated by the QSDFT method, of 0.02 to 0.25. Item 20. The filter according to any one of Items 1 to 19, wherein the ratio (B / A) of the pore volume B (cc / g) of pores having a pore diameter in the range of 3.0 to 3.5 nm among the pore volume calculated by the QSDFT method to the pore volume A (cc / g) of pores having a pore diameter of 2.0 nm or less among the pore volume calculated by the QSDFT method is 0.02 to 0.6. Item 21. The filter according to any one of Items 1 to 20, wherein the ratio (B / C) of the pore volume B (cc / g) of pores having a pore diameter in the range of 3.0 to 3.5 nm among the pore volume calculated by the QSDFT method to the pore volume C (cc / g) of pores having a pore diameter of 2.0 nm or more among the pore volume calculated by the QSDFT method is 0.15 to 0.4. Item 22. The filter according to any one of Items 1 to 21, wherein the activated carbon molded body has a mesopore volume ratio of 10 to 70%. Item 23. The activated carbon molded body has a specific surface area of ​​700 to 1600 m 2 / g. Item 24. The activated carbon molded body 1 cm 2 measured by the following method. 3 The amount of filtered water per unit is 15L / cm 3 24. The filter according to any one of items 1 to 23, wherein <Measurement method> According to NSF / ANSI 53-2021 (DRINKING WATER TREATMENT UNITS-HEALTH EFFECTS, a standard by NSF International based in Michigan, USA), the measurement is performed by the following method. The filter is loaded into a stainless steel housing. The total organic matter concentration (TOC) (concentration of organic matter converted to carbon (C) measured with a TOC meter) is adjusted to 0.5 mg / L or less using an activated carbon filter and hollow fiber membrane, and perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are added to the tap water so that the PFOA concentration is 0.0005±0.00005 mg / L and the PFOS concentration is 0.001±0.00010 mg / L (pH=7.5±0.5, temperature 20±2.5°C, sulfate ion 200±40 mg / L, chloride ion 100±20 mg / L, alkalinity 200±40 mg / L, turbidity less than 1 NTU). The adjusted raw water is continuously passed through the filter loaded in the stainless steel housing at a filtration flow rate of 2 L / min, and the concentrations of PFOS and PFOA before and after passing through the filter are quantitatively measured by solid-phase extraction liquid chromatography mass spectrometry. The point at which the total water concentration of PFOS and PFOA in the effluent water becomes 0.00007 mg / L or more is set as the breakthrough point, and the total amount of filtered water up to the breakthrough point (L) is calculated. The obtained total amount of filtered water (L) is multiplied by the volume (cm) of the activated carbon molded body constituting the filter. 3 ) is the value divided by 1 cm of the activated carbon molding that constitutes the filter. 3 Filtration volume per unit (L / cm 3 ) Item 25. The filter according to any one of Items 1 to 24, wherein the amount of filtrate per 1 g of activated carbon contained in the activated carbon molded body is 30 L / g or more, as measured by the following method. <Measurement method> According to NSF / ANSI 53-2021 (DRINKING WATER TREATMENT UNITS-HEALTH EFFECTS, a standard by NSF International based in Michigan, USA), the measurement is performed by the following method. The filter is loaded into a stainless steel housing. The total organic matter concentration (TOC) (concentration of organic matter converted to carbon (C) measured with a TOC meter) is adjusted to 0.5 mg / L or less using an activated carbon filter and hollow fiber membrane, and perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are added to the tap water so that the PFOA concentration is 0.0005±0.00005 mg / L and the PFOS concentration is 0.001±0.00010 mg / L (pH=7.5±0.5, temperature 20±2.5°C, sulfate ion 200±40 mg / L, chloride ion 100±20 mg / L, alkalinity 200±40 mg / L, turbidity less than 1 NTU). The adjusted raw water is continuously passed through the filter loaded in the stainless steel housing at a filtration flow rate of 2 L / min, and the concentrations of PFOS and PFOA before and after passing through the filter are quantitatively measured by solid-phase extraction liquid chromatography mass spectrometry. The point at which the total water concentration of PFOS and PFOA in the effluent water becomes 0.00007 mg / L or more is set as the breakthrough point, and the total amount of filtered water up to the breakthrough point (L) is calculated. The value obtained by dividing the total amount of filtered water (L) by the total weight of activated carbon contained in the activated carbon molded body constituting the filter is set as the amount of filtered water per 1 g of activated carbon contained in the activated carbon molded body constituting the filter (L / g). Item 26. The activated carbon molded body 1 cm 2 measured by the following method 3 The amount of filtered water per unit is 4L / cm 3 26. The filter according to any one of items 1 to 25, wherein <Measurement method> According to NSF / ANSI 53-2022 (DRINKING WATER TREATMENT UNITS-HEALTH EFFECTS, a standard by NSF International based in Michigan, USA), the measurement is performed by the following method. The filter is loaded into a stainless steel housing. The total organic matter concentration (TOC) (concentration of organic matter converted to carbon (C) measured with a TOC meter) is adjusted to 0.5 mg / L or less using an activated carbon filter and hollow fiber membrane, and perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are added to the tap water so that the PFOA concentration is 0.0005±0.00005 mg / L and the PFOS concentration is 0.001±0.00010 mg / L (pH=7.5±0.5, temperature 20±2.5°C, sulfate ion 200±40 mg / L, chloride ion 100±20 mg / L, alkalinity 200±40 mg / L, turbidity less than 1 NTU). The adjusted raw water is continuously passed through the filter loaded in the stainless steel housing at a filtration flow rate of 2 L / min, and the concentrations of PFOS and PFOA before and after passing through the filter are quantitatively measured by solid-phase extraction liquid chromatography mass spectrometry. The point at which the total water concentration of PFOS and PFOA in the effluent water becomes 0.00002 mg / L or more is set as the breakthrough point, and the total amount of filtered water up to the breakthrough point (L) is calculated. The obtained total amount of filtered water (L) is multiplied by the volume (cm) of the activated carbon molded body constituting the filter. 3 ) is the value divided by 1 cm of the activated carbon molding that constitutes the filter. 3 Filtration volume per unit (L / cm 3 ) Item 27. The filter according to any one of Items 1 to 26, wherein the amount of filtrate per 1 g of activated carbon contained in the activated carbon molded product is 10 L / g or more, as measured by the following method. <Measurement method> According to NSF / ANSI 53-2022 (DRINKING WATER TREATMENT UNITS-HEALTH EFFECTS, a standard by NSF International based in Michigan, USA), the measurement is performed by the following method. The filter is loaded into a stainless steel housing. The total organic matter concentration (TOC) (concentration of organic matter converted to carbon (C) measured with a TOC meter) is adjusted to 0.5 mg / L or less using an activated carbon filter and hollow fiber membrane, and perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are added to the tap water so that the PFOA concentration is 0.0005±0.00005 mg / L and the PFOS concentration is 0.001±0.00010 mg / L (pH=7.5±0.5, temperature 20±2.5°C, sulfate ion 200±40 mg / L, chloride ion 100±20 mg / L, alkalinity 200±40 mg / L, turbidity less than 1 NTU). The adjusted raw water is continuously passed through the filter loaded in the stainless steel housing at a filtration flow rate of 2 L / min, and the concentrations of PFOS and PFOA before and after passing through the filter are quantitatively measured by solid-phase extraction liquid chromatography mass spectrometry. The point at which the total water concentration of PFOS and PFOA in the effluent water becomes 0.00002 mg / L or more is set as the breakthrough point, and the total amount of filtered water up to the breakthrough point (L) is calculated. The value obtained by dividing the total amount of filtered water (L) by the total weight of activated carbon contained in the activated carbon molded body constituting the filter is set as the amount of filtered water per 1 g of activated carbon contained in the activated carbon molded body constituting the filter (L / g). Item 28. The filter according to any one of Items 1 to 27, which is used for removing fluorine-containing organic compounds in water to be treated. Item 29. The filter according to Item 28, wherein the water to be treated is tap water. Item 30. The filter according to item 28 or 29, wherein the fluorine-containing organic compound includes perfluorooctanesulfonic acid and / or perfluorooctanoic acid. Item 31. A method for removing fluorine-containing organic compounds, comprising a step of passing water to be treated that contains fluorine-containing organic compounds through a filter that contains an activated carbon molded body containing activated carbon, the activated carbon molded body having a pore volume A (cc / g) of pores with a pore diameter of 2.0 nm or less of 0.30 cc / g or more and a pore volume B (cc / g) of pores with a pore diameter of 3.0 to 3.5 nm of 0.01 cc / g or more, as calculated by a QSDFT method, to remove the fluorine-containing organic compounds from the water to be treated. Item 32. Superficial velocity (SV) is 2500h -1 Item 32. The method for removing fluorine-containing organic compounds according to Item 31, wherein the water to be treated is passed through under the above conditions. Item 33. A filter for removing fluorine-containing organic compounds in treated water, comprising an activated carbon molded body containing activated carbon, wherein the activated carbon molded body has a pore volume calculated by the QSDFT method in which the pore volume A (cc / g) of pores with a pore diameter of 2.0 nm or less is 0.30 cc / g or more, and the pore volume B (cc / g) of pores with a pore diameter of 3.0 to 3.5 nm is 0.01 cc / g or more. Item 34. For the manufacture of a fluorine-containing organic compound removal filter, the activated carbon molding contains activated carbon, and the pore volume calculated by the QSDFT method is 0.30 cc / g or more for pores with a pore diameter of 2.0 nm or less, and the pore volume B (cc / g) for pores with a pore diameter of 3.0 to 3.5 nm is 0.01 cc / g or more. Item 35. A method for producing the filter according to any one of items 1 to 30, comprising: A method for producing a filter, comprising the steps of pouring a slurry containing at least activated carbon onto a net, dehydrating the slurry, and drying the slurry to produce a sheet-like molded product. Item 36. A method for producing a filter according to any one of items 1 to 30, comprising: A method for manufacturing a filter, comprising the steps of: immersing a core body having a large number of small suction holes on its surface, detachable flanges at both ends, and a filtrate discharge outlet at one end, into a slurry containing at least activated carbon; filtering the slurry while sucking it from the filtrate discharge outlet through the small suction holes; adhering the slurry to the surface of the core body to obtain a slurry molded body; and removing the obtained slurry molded body from the mold body and drying it to produce an activated carbon molded body. Item 37. A method for producing a filter according to any one of items 1 to 30, comprising: A method for manufacturing a filter, comprising the steps of: immersing a core body having a large number of small suction holes on its surface, a nonwoven fabric core provided on the core body, detachable flanges at both ends, and a molding form having a filtrate discharge outlet at one end, in a slurry containing at least activated carbon, filtering the slurry while sucking it from the filtrate discharge outlet through the small suction holes, causing the slurry to adhere to the surface of the nonwoven fabric core to obtain a slurry molded body, and removing the obtained slurry molded body from the molding form and drying it to produce a laminated activated carbon molded body comprising the nonwoven fabric core and the activated carbon molded body. Item 38. The method for producing a filter according to any one of Items 35 to 37, wherein the slurry contains binder fibers. Item 39. The method for producing a filter according to any one of Items 35 to 38, wherein the content of the activated carbon in the slurry is 60 mass % or more based on the total solid content. Effect of the Invention

[0009] The filter of the present invention includes an activated carbon molded body containing activated carbon as a constituent member, and the activated carbon molded body has a pore volume A (cc / g) of pores with a pore diameter of 2.0 nm or less of 0.30 cc / g or more, and a pore volume B (cc / g) of pores with a pore diameter in the range of 3.0 to 3.5 nm of 0.01 cc / g or more, among the pore volumes calculated by the QSDFT method. Therefore, when the superficial velocity (SV) of the water to be treated is high (for example, when the SV is 2500 h -1 Even when the concentration of the fluorine-containing organic compounds is low, the fluorine-containing organic compounds are excellent in removal performance. [Brief description of the drawings]

[0010] [Figure 1] 1 is a graph showing the log differential pore volume distribution of the activated carbon molded body constituting the filter of Example 1, calculated by the QSDFT method. [Diagram 2] 1 is a graph showing the log differential pore volume distribution calculated by the QSDFT method of the activated carbon molded body constituting the filter of Example 2. [Diagram 3] 1 is a graph showing the log differential pore volume distribution calculated by the QSDFT method of the activated carbon molded body constituting the filter of Example 3. [Figure 4] 1 is a graph showing the log differential pore volume distribution calculated by the QSDFT method of the activated carbon molded body constituting the filter of Comparative Example 1. [Diagram 5] 1 is a graph showing the log differential pore volume distribution calculated by the QSDFT method of the activated carbon molded body constituting the filter of Comparative Example 2. [Figure 6] 1 is a graph showing an integrated pore volume distribution of the activated carbon molded body constituting the filter of Example 1, calculated by the QSDFT method. [Figure 7] 1 is a graph showing an integrated pore volume distribution of the activated carbon molded body constituting the filter of Example 2, calculated by the QSDFT method. [Figure 8] 1 is a graph showing an integrated pore volume distribution calculated by a QSDFT method for the activated carbon molded body constituting the filter of Example 3. [Figure 9] 1 is a graph showing an integrated pore volume distribution of the activated carbon molded body constituting the filter of Comparative Example 1, calculated by the QSDFT method. [Figure 10] 1 is a graph showing an integrated pore volume distribution calculated by a QSDFT method for the activated carbon molded body constituting the filter of Comparative Example 2. [Figure 11] FIG. 1 is a schematic diagram of a molding form used in a slurry suction method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The filter of the present invention is a filter including an activated carbon molded body containing activated carbon, and the activated carbon molded body has a pore volume A (cc / g) of pores with a pore diameter of 2.0 nm or less of 0.30 cc / g or more and a pore volume B (cc / g) of pores with a pore diameter in the range of 3.0 to 3.5 nm of 0.01 cc / g or more, as calculated by the QSDFT method. The filter of the present invention will be described in detail below.

[0012] <Physical properties of activated carbon molded body> In the present invention, the pore volume of a specific pore diameter range of the activated carbon molded body is calculated by the QSDFT method. The QSDFT method (Quenched Solid Density Functional Theory) is an analytical method that can calculate the pore volume distribution from about 0.5 nm to about 40 nm, targeting the pore diameter analysis of geometrically and chemically irregular microporous and mesoporous carbons. The QSDFT method is a method that significantly improves the accuracy of pore volume distribution analysis because the effects of roughness and non-uniformity of the pore surface are clearly taken into account. In the present invention, the nitrogen adsorption isotherm is measured using Quantachrome's "AUTOSORB6" and the pore volume distribution is analyzed by the QSDFT method. The pore volume distribution is calculated by applying N2at 77K on carbon [slit pore, QSDFT equilibrium model] as a calculation model to the nitrogen desorption isotherm measured at a temperature of 77K, and the pore volume of a specific pore diameter range of the activated carbon molded body can be calculated.

[0013] Initially, according to the study of the present inventors, it was thought that fluorine-containing organic compounds such as PFOA are easily adsorbed into micropores with a pore diameter of 2.0 nm or less due to their molecular size. However, the present inventors considered that when considering the filtration of fluorine-containing organic compound molecules under conditions of high superficial velocity (SV), the speed at which fluorine-containing organic compound molecules diffuse into the pores is also an important factor. Then, the present inventors conducted repeated studies from these perspectives, and found that a filter having excellent fluorine-containing organic compound removal performance can be obtained even under conditions of high superficial velocity (SV) by controlling the pore diameter and pore volume of the activated carbon molded body constituting the filter, setting the pore volume of pores with a pore diameter of 2.0 nm or less within a specific range, and setting the pore volume of pores with a pore diameter of 3.0 nm or more and 3.5 nm or less as pores contributing to diffusion into the pores within a specific range.

[0014] The activated carbon molded body constituting the filter of the present invention has a pore volume A (cc / g) of pores having a diameter of 2.0 nm or less, calculated by the QSDFT method, of 0.30 cc / g or more. From the viewpoint of easily achieving excellent removal performance of fluorine-containing organic compounds even when the superficial velocity (SV) of the water to be treated is high, the pore volume A is preferably 0.35 cc / g or more and 0.80 cc / g or less, and more preferably 0.35 cc / g or more and 0.660 cc / g or less.

[0015] The activated carbon molded body constituting the filter of the present invention has a pore volume B (cc / g) of pores with diameters in the range of 3.0 to 3.5 nm, calculated by the QSDFT method, of 0.01 cc / g or more, and from the viewpoint of easily achieving excellent removal performance of fluorine-containing organic compounds even when the superficial velocity (SV) of the water to be treated is high, the pore volume B is preferably 0.04 cc / g or more and 0.30 cc / g or less, and more preferably 0.15 cc / g or more and 0.25 cc / g or less.

[0016] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters of 0.65 nm or less is preferably 0.015 cc / g or more and 0.08 cc / g or less, and more preferably 0.04 cc / g or more and 0.07 cc / g or less.

[0017] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters of 1.0 nm or less is preferably 0.15 cc / g or more and 0.35 cc / g or less, and more preferably 0.18 cc / g or more and 0.23 cc / g or less.

[0018] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters of 1.5 nm or less is preferably 0.25 cc / g or more and 0.5 cc / g or less, and more preferably 0.27 cc / g or more and 0.35 cc / g or less.

[0019] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume C of pores with diameters of 2.0 nm or more calculated by the QSDFT method is preferably 0.05 cc / g or more and 0.8 cc / g or less, and more preferably 0.2 cc / g or more and 0.6 cc / g or less, in terms of the activated carbon molded body constituting the filter of the present invention.

[0020] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters in the range of 0.65 to 0.8 nm is preferably 0.05 cc / g or more and 0.1 cc / g or less, and more preferably 0.055 cc / g or more and 0.063 cc / g or less.

[0021] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters in the range of 0.8 to 1.0 nm is preferably 0.05 cc / g or more and 0.25 cc / g or less, and more preferably 0.06 cc / g or more and 0.10 cc / g or less.

[0022] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters in the range of 1.0 to 1.5 nm is preferably 0.08 cc / g or more and 0.20 cc / g or less, and more preferably 0.08 cc / g or more and 0.16 cc / g or less.

[0023] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters in the range of 1.3 to 1.5 nm is preferably 0.001 cc / g or more and 0.08 cc / g or less, more preferably 0.02 cc / g or more and 0.07 cc / g or less, and even more preferably 0.02 cc / g or more and 0.04 cc / g or less.

[0024] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters in the range of 1.5 to 2.0 nm is preferably 0.001 cc / g or more and 0.10 cc / g or less, and more preferably 0.05 cc / g or more and 0.10 cc / g or less.

[0025] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters in the range of 2.0 to 2.5 nm is preferably 0.1 cc / g or less, more preferably 0.02 cc / g or more and 0.09 cc / g or less, and even more preferably 0.06 cc / g or more and 0.09 cc / g or less.

[0026] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters in the range of 2.5 to 3.0 nm is preferably 0.15 cc / g or less, more preferably 0.02 cc / g or more and 0.13 cc / g or less, and even more preferably 0.10 cc / g or more and 0.13 cc / g or less.

[0027] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters in the range of 3.5 to 4.0 nm is preferably 0.1 cc / g or less, more preferably 0.02 cc / g or more and 0.10 cc / g or less, and even more preferably 0.06 cc / g or more and 0.10 cc / g or less.

[0028] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume calculated by the QSDFT method for pores with diameters in the range of 3.0 to 4.0 nm is preferably 0.01 cc / g or more and 0.35 cc / g or less, more preferably 0.07 cc / g or more and 0.30 cc / g or less, and even more preferably 0.23 cc / g or more and 0.30 cc / g or less.

[0029] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume of pores having diameters in the range of 4.0 to 4.5 nm calculated by the QSDFT method is preferably 0.1 cc / g or less, and more preferably 0.03 cc / g or less, of the activated carbon molded body constituting the filter of the present invention.

[0030] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the pore volume of pores with diameters of 4.0 nm or more calculated by the QSDFT method is preferably 0.05 cc / g or more and 0.13 cc / g or less, and more preferably 0.09 cc / g or more and 0.12 cc / g or less.

[0031] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the activated carbon molded body constituting the filter of the present invention has a total pore volume T calculated by the QSDFT method of preferably 0.4 cc / g or more and 1.2 cc / g or less, more preferably 0.6 cc / g or more and 1.1 cc / g or less, and even more preferably 0.85 cc / g or more and 1.1 cc / g or less.

[0032] In order to facilitate achieving excellent removal performance of fluorine-containing organic compounds even when the superficial velocity (SV) of the water to be treated is high, the ratio (A / T) of the pore volume A (cc / g) of pores having a pore diameter of 2.0 nm or less out of the total pore volume T (cc / g) calculated by the QSDFT method is preferably 0.3 to 0.9, more preferably 0.35 to 0.7, and even more preferably 0.35 to 0.45, of the activated carbon molded body constituting the filter of the present invention.

[0033] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the ratio (B / T) of the pore volume B (cc / g) of pores with diameters in the range of 3.0 to 3.5 nm among the pore volume calculated by the QSDFT method to the total pore volume T (cc / g) calculated by the QSDFT method is preferably 0.02 to 0.25, more preferably 0.08 to 0.25, and even more preferably 0.17 to 0.25.

[0034] In order to facilitate achieving excellent fluorine-containing organic compound removal performance even when the superficial velocity (SV) of the water to be treated is high, the ratio (B / A) of the pore volume B (cc / g) of pores having pore diameters in the range of 3.0 to 3.5 nm among the pore volume calculated by the QSDFT method to the pore volume A (cc / g) of pores having pore diameters of 2.0 nm or less among the pore volume calculated by the QSDFT method is preferably 0.02 to 0.6, more preferably 0.1 to 0.6, and even more preferably 0.4 to 0.6.

[0035] In order to facilitate achieving excellent removal performance of fluorine-containing organic compounds in the activated carbon molded body constituting the filter of the present invention even when the superficial velocity (SV) of the water to be treated is high, the ratio (B / C) of the pore volume B (cc / g) of pores with pore diameters in the range of 3.0 to 3.5 nm among the pore volume calculated by the QSDFT method to the pore volume C (cc / g) of pores with pore diameters of 2.0 nm or more among the pore volume calculated by the QSDFT method is preferably 0.15 to 0.4, more preferably 0.24 to 0.4, and even more preferably 0.32 to 0.38.

[0036] The activated carbon molded body constituting the filter of the present invention preferably has a mesopore volume ratio of 10 to 70%, more preferably 30 to 70%, and even more preferably 50 to 70%, from the viewpoint of easily achieving excellent removal performance of fluorine-containing organic compounds even when the superficial velocity (SV) of the water to be treated is high. In the present invention, the mesopore volume ratio is a value calculated by the following formula. (Formula) (mesopore volume ratio (%)) = ((total pore volume T (cc / g) calculated by QSDFT method)) - (pore volume A (cc / g) of pores with a pore diameter of 2.0 nm or less among the pore volume calculated by QSDFT method)) / (total pore volume T (cc / g) calculated by QSDFT method × 100

[0037] The activated carbon molded body constituting the filter of the present invention has a specific surface area of ​​700 to 1600 m2 in order to easily obtain the above-mentioned pore distribution. 2 / g, and 900 to 1400m 2 / g is more preferable, and 1000 to 1300m 2 / g is more preferable. Here, the specific surface area of ​​the activated carbon molded body is a value calculated based on the nitrogen adsorption isotherm at 77.4K. Specifically, the nitrogen adsorption isotherm is created as follows. A sample of the activated carbon molded body to be measured is cooled to 77.4K (the boiling point of nitrogen), nitrogen gas is introduced, and the adsorption amount V [cc / g] of the nitrogen gas is measured by the volumetric method. At this time, the pressure P [hPa] of the introduced nitrogen gas is gradually increased, and the value divided by the saturated vapor pressure P0 [hPa] of the nitrogen gas is set as the relative pressure P / P0, and the adsorption amount for each relative pressure is plotted to create a nitrogen adsorption isotherm. The adsorption amount of nitrogen gas can be measured using a commercially available automatic gas adsorption amount measuring device (for example, the product name "AUTOSORB6" (manufactured by QUANTACHROME)). In the present invention, the specific surface area is calculated according to the BET method based on the nitrogen adsorption isotherm. This analysis can be performed using known means such as an analysis program attached to the above device.

[0038] <Ingredients contained in activated carbon molded body> (activated carbon) The activated carbon molded body constituting the filter of the present invention contains at least activated carbon. The form of the activated carbon is not particularly limited, but examples thereof include granular activated carbon, powdered activated carbon, and fibrous activated carbon. These activated carbons may be used alone or in combination of two or more.

[0039] The activated carbon is not particularly limited as long as an activated carbon molded body having the above-mentioned physical properties can be obtained. The pore size, pore volume, mesopore volume ratio, and specific surface area of ​​the activated carbon molded body described above are basically derived from the pore size, pore volume, mesopore volume ratio, and specific surface area of ​​the raw activated carbon, so that the pore size, pore volume, mesopore volume ratio, and specific surface area of ​​the raw activated carbon can be appropriately adjusted to obtain an activated carbon molded body having the above-mentioned physical properties. In addition, the physical properties of the activated carbon molded body may be adjusted to a desired value by combining two or more types of activated carbon having different pore sizes and pore volumes. The pore size, pore volume, mesopore volume ratio, and specific surface area of ​​the activated carbon can be adjusted to a desired value by appropriately adjusting the activation conditions (activation temperature, activation gas, etc.) when producing the activated carbon. The pore size, pore volume, mesopore volume ratio, and specific surface area of ​​the activated carbon can be measured by the same method as described in the above section "Physical properties of activated carbon molded body". Examples of commercially available activated carbon for obtaining activated carbon molded body having the above physical properties include "W-15W" (fibrous activated carbon) manufactured by A-DOLL Co., Ltd. and "TC-100N" (granular activated carbon) manufactured by Osaka Gas Chemicals Co., Ltd.

[0040] The content of activated carbon in the activated carbon molded body constituting the filter of the present invention is not particularly limited, but is usually about 60% by mass or more, and from the viewpoint of making it easier to obtain an activated carbon molded body having the above-mentioned physical properties and from the viewpoint of improving the removal performance of fluorine-containing organic compounds, the content is preferably 60 to 98% by mass, and more preferably 70 to 98% by mass.

[0041] (binder fiber) The activated carbon molded body constituting the filter of the present invention may contain binder fibers. The binder fibers are integrated with the activated carbon to entangle the activated carbon and form it into a filter shape. Examples of the binder fibers include heat-fusible fibers and pulp.

[0042] The heat-fusible fiber is a fiber that exhibits fusion characteristics by heating. The heat-fusible component contained in the heat-fusible fiber preferably has a melting point of 80 to 170°C, more preferably 80 to 140°C. Specific examples of the heat-fusible component include polyolefin resins such as polyethylene and polypropylene, and polyester resins such as copolymerized polyethylene terephthalate in which a copolymerization component such as isophthalic acid is copolymerized. In addition, the heat-fusible fiber may be a fully fused type consisting of only a single heat-fusible component, or a core-sheath type heat-fusible fiber in which a heat-fusible component is arranged in the sheath and a synthetic resin component whose melting point is preferably 20°C or higher, more preferably 30°C or higher than the melting point of the sheath is arranged in the core. Among them, from the viewpoint of further increasing the strength of the activated carbon molded body, a core-sheath type heat-fusible short fiber is preferable. In the sheath-core type heat-fusible staple fiber, the core component is not particularly limited, but may be, for example, a synthetic resin having a melting point of 150 to 300°C, more preferably 200 to 300°C, and having a melting point 20°C or more higher than that of the heat-fusible component of the sheath. An example of the synthetic resin is polyethylene terephthalate. An example of the heat-fusible component of the sheath is copolymerized polyethylene terephthalate in which isophthalic acid is copolymerized. The heat-fusible fibers may be used alone or in combination of two or more.

[0043] The fineness of the heat-fusible fiber is not particularly limited, but may be, for example, about 0.5 to 5.0 dtex, preferably 1.0 to 3.0 dtex. In the present invention, the fineness of the heat-fusible fiber is a value (average value of 5 measurements) obtained by measurement based on "Method A" specified in "8.5.1 Correct fineness" of JIS L 1015:2021 (chemical fiber staple test method).

[0044] The fiber length of the heat-fusible fiber is not particularly limited, but may be, for example, about 10 to 100 mm, preferably 30 to 70 mm. In the present invention, the fiber length of the heat-fusible fiber is a value (average value of 200 fibers) obtained by measurement based on the "direct method (C method)" specified in "8.4.1 Average fiber length" of JIS L 1015:2021 (chemical fiber staple test method).

[0045] The fiber diameter of the heat-fusible fiber is not particularly limited, but may be, for example, about 1 to 20 μm, and preferably 5 to 15 μm. In the present invention, the fiber diameter of the heat-fusible fiber is a value obtained by observing the cross section of the heat-fusible fiber under a microscope and measuring the length.

[0046] The pulp contributes to further improving the mechanical strength of the activated carbon molded body. The freeness of the pulp is not particularly limited, but is preferably 1 to 300 ml, more preferably 10 to 200 ml. In the present invention, the freeness of the pulp is a value (average value of two measurement results) obtained by measurement based on JIS P 8121-2:2012 (Pulp-Freeness Test Method-Part 2: Canadian Standard Freeness Method). The fiber length of the pulp is not particularly limited, but is preferably 0.1 to 3 mm. Examples of the pulp include acrylic pulp, polyolefin pulp, aramid pulp, wood pulp, and hemp pulp.

[0047] The content of the binder fiber contained in the activated carbon molded body constituting the filter of the present invention affects the pore volume, mesopore volume ratio, and specific surface area of ​​the activated carbon molded body, so it is necessary to appropriately adjust the pore volume, mesopore volume ratio, and specific surface area of ​​the activated carbon molded body to the target values. The total content of the binder fiber contained in the activated carbon molded body constituting the filter of the present invention is usually about 40% by mass or less in order to easily adjust the pore volume, mesopore volume ratio, and specific surface area of ​​the activated carbon molded body to the target values, and is preferably 2 to 35% by mass, more preferably 3 to 30% by mass from the viewpoint of making it easier to obtain an activated carbon molded body having the above-mentioned physical properties, improving the mechanical strength of the activated carbon molded body, and improving the removal performance of fluorine-containing organic compounds. In addition, when the activated carbon molded body contains a heat-fusible fiber, the content of the heat-fusible fiber is, for example, about 1 to 30% by mass, and from the above viewpoint, is preferably 3 to 30% by mass, more preferably 5 to 25% by mass, and more preferably 10 to 20% by mass. When the activated carbon molded body contains pulp, the pulp content is, for example, about 1 to 20 mass %, and from the above viewpoint, preferably 2 to 15 mass %, more preferably 3 to 10 mass %.

[0048] (Other Ingredients) The activated carbon molded body constituting the filter of the present invention may contain other components as necessary in addition to the activated carbon and the binder fiber. Examples of the other components include components capable of removing lead. Examples of the components capable of removing lead include ion exchange fibers, ion exchange resins, chelating fibers, chelating resins, titanium silicate, zeolites, etc. These components may be used alone or in combination of two or more. The content ratio of the other components contained in the activated carbon molded body constituting the filter of the present invention is not particularly limited, but is usually about 5 mass% or less, preferably 3 mass% or less, and more preferably 2 mass% or less.

[0049] <Manufacturing method of activated carbon molded body> The method for producing the activated carbon molded body constituting the filter of the present invention is not particularly limited, and a known method can be applied using the activated carbon and, if necessary, the binder fiber and / or other components. Examples of the method for producing the activated carbon molded body constituting the filter of the present invention include a wet method, a dry method, and a slurry suction method.

[0050] The method for producing a sheet-like activated carbon molded body by the wet method is not particularly limited, and examples thereof include the following methods. First, activated carbon and binder fibers and / or other components that are blended as necessary are mixed and sheared using a device such as a pulper, beater, or refiner to prepare a slurry in which the activated carbon is uniformly dispersed in water. The content of activated carbon in the slurry is preferably 60% by mass or more, more preferably 60 to 98% by mass, and even more preferably 70 to 98% by mass, based on the total solid content (components other than water), from the viewpoint of facilitating the production of an activated carbon molded body having the above-mentioned physical properties. The obtained slurry is poured onto a net (wire) at a predetermined flow rate and dehydrated to adjust the basis weight. Thereafter, the sheet is dried in a dryer part through a press part, and the sheet surface is smoothed in a calendar part, and then the sheet is molded into a sheet (nonwoven fabric) by a known technique such as winding on a reel, to obtain an activated carbon molded body that is a sheet-like molded body. The thickness of the sheet-like molded body can be adjusted to a desired thickness using a heat press roller or the like. A cylindrical activated carbon molded body can be obtained, for example, by winding a sheet-like molded body produced by a wet method several times around a cylindrical core to a predetermined thickness, heat-treating the molded body in that state, cooling the molded body, and then removing the core. When producing a cylindrical activated carbon molded body, it is preferable that the molded body contains fibrous activated carbon and also contains heat-fusible short fibers as binder fibers.

[0051] The method for producing a sheet-like activated carbon molded body by the dry method is not particularly limited, but examples thereof include a method in which activated carbon and binder fibers and / or other components blended as necessary are used to form a short fiber structure sheet (nonwoven fabric) by airlaid or carding (card web method) to obtain an activated carbon molded body that is a sheet-like molded body, and a method in which the sheet-like molded body is needle-punched to form a needle-punched sheet (needle-punched nonwoven fabric) that is laminated and integrated to obtain an activated carbon molded body that is a laminated sheet-like molded body. In addition, a cylindrical activated carbon molded body can be obtained by, for example, winding a sheet-like molded body or a laminated sheet-like molded body produced by the dry method several times around a cylindrical core to a predetermined thickness, heat-treating it in that state, cooling it, and then removing the core. When producing a cylindrical activated carbon molded body, it is preferable to include fibrous activated carbon, and it is also preferable to include heat-fusible short fibers as binder fibers.

[0052] The method for producing the activated carbon molded body by the slurry suction method is not particularly limited, and examples thereof include the following methods. First, activated carbon, and binder fibers and / or other components that are blended as necessary are mixed with water to obtain a slurry. The content of activated carbon in the slurry is preferably 60% by mass or more, more preferably 60 to 98% by mass, and even more preferably 70 to 98% by mass, based on the total solid content (components other than water), from the viewpoint of facilitating the production of an activated carbon molded body having the above-mentioned physical properties. Next, a molding frame is immersed in the slurry. As an example of the molding frame 1, as shown in FIG. 11, there is one having a large number of small suction holes 3 on the surface of a cylindrical core body 2, detachable flanges 4, 4' at both ends, and a filtrate outlet 5 at one end. Then, the slurry is filtered while being sucked from the filtrate outlet 5 through the small suction holes 3 using a suction pump or the like, and the slurry is attached to the surface of the core body 2 to obtain a slurry molded body. The obtained slurry molded body is dried to obtain an activated carbon molded body. Alternatively, a cylindrical nonwoven fabric core, which will be described later, may be set on the core body 2, and the slurry may be attached to the surface of the nonwoven fabric core in the same manner as above to obtain a slurry molded body in which the nonwoven fabric core and the activated carbon layer (the layer that will become the activated carbon molded body) are integrated. The obtained slurry molded body is dried to obtain a laminated activated carbon molded body in which the nonwoven fabric core and the activated carbon molded body are integrated. Examples of the obtained activated carbon molded body and laminated activated carbon molded body include those in which the activated carbon is entangled with binder fibers such as pulp to maintain its shape. The slurry molded body may be subjected to a heat treatment or a compression treatment as necessary. In the slurry suction method, the shape of the activated carbon molded body corresponds to the shape of the molding frame or the nonwoven fabric core, so that the shape of the activated carbon molded body can be made into various shapes by changing the shape of the molding frame or the nonwoven fabric core.

[0053] <Molding of activated carbon> The shape of the activated carbon molded body constituting the filter of the present invention is not particularly limited, and examples thereof include a sheet shape, a disk shape, a columnar shape, and a cylindrical shape, with the cylindrical shape being preferred.

[0054] When the activated carbon molded body is cylindrical, the height of the activated carbon molded body is not particularly limited, but may be, for example, 10 to 250 mm, and preferably 20 to 100 mm. The outer diameter of the activated carbon molded body is not particularly limited, but may be, for example, 10 to 50 mm, and preferably 20 to 45 mm. The inner diameter of the activated carbon molded body is not particularly limited, but may be, for example, 5 to 30 mm, and preferably 10 to 20 mm. The thickness of the activated carbon molded body is not particularly limited, but may be, for example, 5 to 45 mm, and preferably 10 to 35 mm. The volume of the activated carbon molded body is, for example, 1 to 500 cm. 3 and preferably 10 to 100 cm 3 More preferably, the length is 10 to 50 cm. 3 Examples include:

[0055] <Filter components> The filter of the present invention includes at least the activated carbon molded body. When the activated carbon molded body is cylindrical, it may include a cylindrical core. The cylindrical core has pores through which the water to be treated can pass, and serves as a core member to increase the strength of the filter and to reduce the falling off of coal dust from the activated carbon molded body.

[0056] The material of the cylindrical core is not particularly limited, and known materials can be used, such as porous ceramics, porous metal filters, nonwoven fabrics, etc. Also, a cylindrical core made of a resin, metal, etc., and molded into a cylindrical shape from a member having fine holes may be used. Among these, a nonwoven fabric core is preferred, and one obtained by compression molding a nonwoven fabric is more preferred. Also, the nonwoven fabric core may be integrated with an activated carbon molded body to form a part of a laminated activated carbon molded body. The fiber material constituting the nonwoven fabric is not particularly limited, and examples thereof include synthetic fibers, and polyester fibers are preferred. Also, the cylindrical core may not contain activated carbon.

[0057] The cylindrical nonwoven core may be, for example, a molded product formed by winding a nonwoven fabric containing heat-fusible staple fibers, and containing at least a part of the heat-fusible component of the heat-fusible staple fibers in a state of being heat-fused to other heat-fusible staple fibers. By configuring the nonwoven core in this way, the heat-fusible staple fibers are arranged three-dimensionally randomly, and by further subjecting the heat-fusible fibers to heat treatment, the heat-fusible fibers are present in the nonwoven fabric in a relatively hard state and with the fiber axis direction partially oriented in the thickness direction, which makes it easier to suppress a decrease in flow rate. The heat-fusible component in the heat-fusible staple fibers preferably has a melting point (softening point if there is no melting point, the same applies below) of 80 to 170°C, more preferably 80 to 140°C. Specific examples of the heat-fusible component include polyolefin resins such as polyethylene and polypropylene, and polyester resins such as copolymerized polyethylene terephthalate in which a copolymerization component such as isophthalic acid is copolymerized. Among them, from the viewpoint of relatively high hydrophilicity and better water compatibility, which leads to improved flow rate, the heat-fusible component is preferably a polyester, and more preferably a copolymerized polyethylene terephthalate copolymerized with isophthalic acid. In the present invention, the melting point is defined as the temperature at which the extreme value of the melting absorption curve measured at a heating rate of 20°C / min using a differential scanning calorimeter (DSC7 manufactured by PerkinElmer Co., Ltd.) is given. The heat-fusible staple fiber may be a fully melted type composed of only a single heat-fusible component, or a core-sheath type heat-fusible staple fiber in which a heat-fusible component is arranged in the sheath and a synthetic resin component in the core, the melting point of which is preferably 20°C or higher, more preferably 30°C or higher than the melting point of the sheath. Among them, from the viewpoint of further increasing the strength of the filter, a core-sheath type heat-fusible staple fiber is preferred. In the sheath-core type heat-fusible staple fiber, the core component is not particularly limited, and examples thereof include a synthetic resin component having a melting point of 150 to 300°C, more preferably 200 to 300°C, and having a melting point 20°C or more higher than that of the heat-fusible component of the sheath. An example of the synthetic resin component is polyethylene terephthalate. An example of the heat-fusible component of the sheath is copolymerized polyethylene terephthalate in which isophthalic acid is copolymerized. The heat-fusible staple fiber may be used alone or in combination of two or more types.

[0058] The filter of the present invention may include a cover layer laminated on the activated carbon molded body. The cover layer has pores through which the water to be treated can pass, and serves to reduce the falling off of coal dust from the activated carbon molded body. When the activated carbon molded body is cylindrical, a cover layer covering the outer peripheral surface and / or the inner peripheral surface of the cylinder may be provided. The cover layer is not particularly limited, but preferred examples include fabrics such as woven fabrics, knitted fabrics, and nonwoven fabrics, and preferred examples include nonwoven fabrics. Among these, nonwoven fabrics made of long fibers or continuous fibers are preferred from the viewpoints of relatively high tear strength and superior handling and processability.

[0059] In the case where the activated carbon molded body is cylindrical, the filter of the present invention may be provided with end caps covering the upper and lower surfaces of the cylinder. The end caps are not particularly limited, and examples thereof include stainless steel, rubber, resin, and other materials that can withstand long-term water passage. Examples of adhesives for the end caps include urethane resin adhesives, epoxy resin adhesives, and isocyanate resin adhesives that have durability when water is passed through for a long period of time and have high sealing properties for the end faces of the filter using only resin.

[0060] <Filter properties> The filter of the present invention is a filter comprising an activated carbon molded body containing activated carbon, and among the pore volumes of the activated carbon molded body calculated by the QSDFT method, the pore volume A (cc / g) of pores having a pore diameter of 2.0 nm or less is 0.30 cc / g or more, and the pore volume B (cc / g) of pores having a pore diameter in the range of 3.0 to 3.5 nm is 0.01 cc / g or more. Therefore, even when the superficial velocity (SV) of the water to be treated is high, the filter has excellent performance for removing fluorine-containing organic compounds.

[0061] The fluorine-containing organic compound removal performance of the filter of the present invention is measured by the following method. 3 Filtration volume per unit (L / cm 3 ), but preferably 15 L / cm 3 More preferably, 20 L / cm 3The above are preferred, and 40 L / cm is even more preferred. 3 The upper limit is not particularly limited, but for example, 80 L / cm 3 and 60 L / cm 3 Examples include:

[0062] <Measurement method> According to NSF / ANSI 53-2021 (DRINKING WATER TREATMENT UNITS-HEALTH EFFECTS, a standard by NSF International based in Michigan, USA), the measurement is performed by the following method. The filter is loaded into a stainless steel housing. The total organic matter concentration (TOC) (concentration of organic matter converted to carbon (C) measured with a TOC meter) is adjusted to 0.5 mg / L or less using an activated carbon filter and hollow fiber membrane, and perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are added to the tap water so that the PFOA concentration is 0.0005±0.00005 mg / L and the PFOS concentration is 0.001±0.00010 mg / L (pH=7.5±0.5, temperature 20±2.5°C, sulfate ion 200±40 mg / L, chloride ion 100±20 mg / L, alkalinity 200±40 mg / L, turbidity less than 1 NTU). The adjusted raw water is continuously passed through the filter loaded in the stainless steel housing at a filtration flow rate of 2 L / min, and the concentrations of PFOS and PFOA before and after passing through the filter are quantitatively measured by solid-phase extraction liquid chromatography mass spectrometry. The point at which the total water concentration of PFOS and PFOA in the effluent water (water that has passed through the filter) becomes 0.00007 mg / L or more is set as the breakthrough point, and the total amount of filtered water (L) up to the breakthrough point is calculated. The obtained total amount of filtered water (L) is multiplied by the volume (cm) of the activated carbon molded body that constitutes the filter. 3 ) is the value divided by 1 cm of the activated carbon molding that constitutes the filter. 3 Filtration volume per unit (L / cm 3 )

[0063] The removal performance of the fluorine-containing organic compound provided by the filter of the present invention is preferably 30 L / g or more, more preferably 100 L / g or more, and even more preferably 150 L / g or more, in terms of the amount of filtrate per 1 g of activated carbon contained in the activated carbon molded body, as measured by the following method. The upper limit is not particularly limited, but may be, for example, 300 L / g or 250 L / g. <Measurement method> 1 cm of the activated carbon molded body constituting the filter of the present invention, measured in accordance with NSF / ANSI 53-2021 3 Filtration volume per unit (L / cm 3 In the same manner as in the measurement method of ), the point where the total concentration of PFOS and PFOA in the effluent water is 0.00007 mg / L or more is set as the breakthrough point, and the total amount of filtered water up to the breakthrough point (L) is calculated. The value obtained by dividing the total amount of filtered water (L) by the total weight of activated carbon contained in the activated carbon molded body constituting the filter is determined as the amount of filtered water per gram of activated carbon contained in the activated carbon molded body constituting the filter of the present invention (L / g).

[0064] The fluorine-containing organic compound removal performance of the filter of the present invention is measured by the following method. 3 Filtration volume per unit (L / cm 3 ) but preferably 4 L / cm 3 The above are preferred, and 6 L / cm 3 The above are preferred, and 20 L / cm is more preferred. 3 The upper limit is not particularly limited, but for example, 60 L / cm 3 and 50 L / cm 3 Examples include:

[0065] <Measurement method> According to NSF / ANSI 53-2022 (DRINKING WATER TREATMENT UNITS-HEALTH EFFECTS, a standard by NSF International based in Michigan, USA), the measurement is performed by the following method. The filter is loaded into a stainless steel housing. The total organic matter concentration (TOC) (concentration of organic matter converted to carbon (C) measured with a TOC meter) is adjusted to 0.5 mg / L or less using an activated carbon filter and hollow fiber membrane, and perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are added to the tap water so that the PFOA concentration is 0.0005±0.00005 mg / L and the PFOS concentration is 0.001±0.00010 mg / L (pH=7.5±0.5, temperature 20±2.5°C, sulfate ion 200±40 mg / L, chloride ion 100±20 mg / L, alkalinity 200±40 mg / L, turbidity less than 1 NTU). The adjusted raw water is continuously passed through the filter loaded in the stainless steel housing at a filtration flow rate of 2 L / min, and the concentrations of PFOS and PFOA before and after passing through the filter are quantitatively measured by solid-phase extraction liquid chromatography mass spectrometry. The point at which the total water concentration of PFOS and PFOA in the effluent water (water that has passed through the filter) becomes 0.00002 mg / L or more is set as the breakthrough point, and the total amount of filtered water (L) up to the breakthrough point is calculated. The total amount of filtered water obtained (L) is multiplied by the volume (cm) of the activated carbon molded body that constitutes the filter. 3 ) is the value divided by 1 cm of the activated carbon molding that constitutes the filter. 3 Filtration volume per unit (L / cm 3 )

[0066] The removal performance of the fluorine-containing organic compound provided by the filter of the present invention is preferably 10 L / g or more, more preferably 30 L / g or more, and even more preferably 100 L / g or more, in terms of the amount of filtered water per 1 g of activated carbon contained in the activated carbon molded body, as measured by the following method. The upper limit is not particularly limited, but may be, for example, 250 L / g or 200 L / g. <Measurement method> 1 cm of the activated carbon molded body constituting the filter of the present invention, measured in accordance with NSF / ANSI 53-2022 3 Filtration volume per unit (L / cm 3 In the same manner as in the measurement method of ), the point where the total concentration of PFOS and PFOA in the effluent water is 0.00002 mg / L or more is set as the breakthrough point, and the total amount of filtered water up to the breakthrough point (L) is calculated. The value obtained by dividing the total amount of filtered water (L) by the total weight of activated carbon contained in the activated carbon molded body constituting the filter is determined as the amount of filtered water per gram of activated carbon contained in the activated carbon molded body constituting the filter of the present invention (L / g).

[0067] In the above-mentioned measurement method, the activated carbon filter and hollow fiber membrane may be commercially available. The TOC meter may be, for example, TOC-5000 manufactured by Shimadzu Corporation.

[0068] <Filter uses, etc.> The filter of the present invention is used as a water purification filter for removing various harmful substances, particularly PFAS, contained in the water to be treated. Examples of the water to be treated include tap water, industrial wastewater, and domestic wastewater, and preferably tap water. Examples of PFAS include perfluorohexane sulfonic acid (PFHxS), perfluorocarboxylic acids (PFCAs), perfluorohexanoic acid (PFHxA), and perfluorobutane sulfonic acid (PFBS), in addition to PFOA and PFOS. The filter of the present invention is particularly excellent in removing PFOS and PFOA, and is therefore suitable for use in removing PFOS and / or PFOA from the water to be treated that contains PFOS and / or PFOA.

[0069] The filter of the present invention is suitable for treating water with a high superficial velocity (SV), for example, when the SV is 2500 h -1 More than 3000h -1 or more, or 3500h -1 Even under the above conditions, it has excellent PFAS removal performance.

[0070] The method for removing fluorine-containing organic compounds of the present invention is characterized in that it comprises an activated carbon molded body containing activated carbon, and the activated carbon molded body includes a filter having a pore volume A (cc / g) of pores with a pore diameter of 2.0 nm or less of 0.30 cc / g or more and a pore volume B (cc / g) of pores with a pore diameter of 3.0 to 3.5 nm of 0.01 cc / g or more, among pore volumes calculated by a QSDFT method, of which the fluorine-containing organic compounds are removed from the water to be treated. The water to be treated is preferably tap water. The fluorine-containing organic compounds preferably include perfluorooctane sulfonic acid and / or perfluorooctanoic acid.

[0071] The present invention also relates to use of a filter including an activated carbon molded body containing activated carbon for removing fluorine-containing organic compounds from water to be treated, wherein the activated carbon molded body is characterized in that, of the pore volume calculated by the QSDFT method, the pore volume A (cc / g) of pores having a pore diameter of 2.0 nm or less is 0.30 cc / g or more, and the pore volume B (cc / g) of pores having a pore diameter in the range of 3.0 to 3.5 nm is 0.01 cc / g or more.

[0072] The present invention also relates to use of an activated carbon molded body for producing a fluorine-containing organic compound removal filter, wherein the activated carbon molded body contains activated carbon and is characterized in that, in the pore volume calculated by the QSDFT method, the pore volume A (cc / g) of pores with a pore diameter of 2.0 nm or less is 0.30 cc / g or more, and the pore volume B (cc / g) of pores with a pore diameter in the range of 3.0 to 3.5 nm is 0.01 cc / g or more.

[0073] In the above-mentioned method for removing fluorine-containing organic compounds of the present invention and the use of the filter of the present invention, the superficial velocity of the water to be treated (the flow rate relative to the volume of the activated carbon molded body) is 2500 h -1 It can be more than that. EXAMPLES

[0074] The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to the examples.

[0075] <Example 1> 1. Preparation of raw materials for activated carbon molding In producing the activated carbon molded body, the following raw materials were prepared. Fibrous activated carbon A (manufactured by A-DOLL Co., Ltd., product name "W-15W") Fibrous activated carbon B (manufactured by A-DOLL Co., Ltd., product name "A-15") -Heat-fusible staple fiber (heat-fusible staple fiber with polyethylene terephthalate copolymerized with isophthalic acid as a heat-fusible component in the sheath and polyethylene terephthalate in the core; the sheath has a melting point of 110°C, the core has a melting point of 260°C, the fiber length is 51mm, the fiber diameter is 12μm, and the fineness is 2.2dtex) Pulp (product name: Vipal (registered trademark), manufactured by Nippon Exlan Kogyo Co., Ltd., fibrillated acrylic fiber, freeness: 50 ml)

[0076] 2. Manufacturing of nonwoven fabric that will become activated carbon molded bodies The above prepared raw materials were mixed using a pulper so that the mass ratio of each raw material in the activated carbon molded body was as shown in Table 1, and a uniformly dispersed slurry was prepared. The obtained slurry was poured onto a wire at a predetermined flow rate and dehydrated to adjust the basis weight. After that, the sheet was dried in a dryer part through a press part, and the sheet surface was smoothed in a calendar part before being wound on a reel. The sheet was then hot-pressed at 110°C with a hot press roller to obtain a wet nonwoven fabric containing activated carbon.

[0077] 3. Manufacturing of activated carbon molded bodies A cylindrical iron pipe with an outer diameter of 10 mm was prepared as a core, and the wet nonwoven fabric containing the activated carbon was wound around the core several times to a predetermined thickness. The wet nonwoven fabric was then placed in a furnace in a wound state, and heat-treated at an atmospheric temperature of 150°C for 2 hours, and then naturally cooled. The core was then removed, and the nonwoven fabric was cut to a length of 60 mm with a cutter to obtain an activated carbon molded body. The height (length) of the obtained activated carbon molded body was 60 mm, the outer diameter was 30 mm, the inner diameter was 10 mm, the mass was 10.3 g, and the mass of the activated carbon contained in the activated carbon molded body was 7.5 g.

[0078] <Example 2> 1. Preparation of raw materials for activated carbon molding In producing the activated carbon molded body, the following raw materials were prepared. Fibrous activated carbon A (manufactured by A-DOLL Co., Ltd., product name "W-15W") Pulp (product name: Vipal (registered trademark), manufactured by Nippon Exlan Kogyo Co., Ltd., fibrillated acrylic fiber, freeness: 50 ml)

[0079] 2. Manufacturing of nonwoven core A thin web was formed by carding heat-fusible staple fibers (polyethylene terephthalate copolymerized with isophthalic acid as a heat-fusible component in the sheath and polyethylene terephthalate in the core, the melting point of the sheath was 110°C, the melting point of the core was 260°C, the fiber length was 51 mm, the fiber diameter was 12 μm, and the fineness was 2.2 dtex). The web was then needle-punched and heat-pressed at a temperature of 170°C, and cooled to obtain a nonwoven fabric. Next, an iron cylindrical pipe with an outer diameter of 10 mm was prepared as the core, and the nonwoven fabric was wound around the core several times to a predetermined thickness so that the outer diameter of the nonwoven fabric core was 12 mm. The nonwoven fabric was then placed in a furnace and heat-treated at an atmospheric temperature of 150°C for 1 hour, and then naturally cooled. After removing the core, the nonwoven fabric was cut to a length of 56 mm with a cutter to obtain a nonwoven fabric core. The resulting nonwoven core had an inner diameter of 10 mm, an outer diameter of 12 mm, and an apparent density of 0.35 g / cm. 3 It was.

[0080] 3. Manufacturing of laminated activated carbon molded bodies The raw materials prepared above were dispersed in water so that the mass ratio of each raw material in the activated carbon molded body was as shown in Table 1, to obtain a slurry. The nonwoven fabric core prepared was set in the core body 2 of the molded form 1 shown in FIG. 11, and the molded form was immersed in the slurry. Then, the slurry was filtered while being sucked from the filtrate outlet 5 through the small suction hole 3 using a suction pump, so that the slurry was attached to the surface of the nonwoven fabric core, and a slurry molded body in which the nonwoven fabric core and the activated carbon layer (the layer that becomes the activated carbon molded body) were integrated was obtained. The obtained slurry molded body was pulled out of the molded form, and the slurry molded body was dried in a drying furnace at 120° C. for 15 hours to obtain a cylindrical laminated activated carbon molded body (a laminate of a nonwoven fabric core and an activated carbon molded body) with an outer diameter of 30 mm, an inner diameter of 12 mm, and a length of 56 mm. The mass of the obtained activated carbon molded body was 9.9 g, and the mass of the activated carbon contained in the activated carbon molded body was 9.4 g.

[0081] <Example 3> 1. Preparation of raw materials for activated carbon molding In producing the activated carbon molded body, the following raw materials were prepared. Granular activated carbon C (product name "TC-100N" manufactured by Osaka Gas Chemicals Co., Ltd.) Pulp (product name: Vipal (registered trademark), manufactured by Nippon Exlan Kogyo Co., Ltd., fibrillated acrylic fiber, freeness: 50 ml)

[0082] 2. Manufacturing of nonwoven core A thin web was formed by carding heat-fusible staple fibers (polyethylene terephthalate copolymerized with isophthalic acid as a heat-fusible component in the sheath and polyethylene terephthalate in the core, the melting point of the sheath was 110°C, the melting point of the core was 260°C, the fiber length was 51 mm, the fiber diameter was 12 μm, and the fineness was 2.2 dtex). The web was then needle-punched and heat-pressed at a temperature of 170°C, and cooled to obtain a nonwoven fabric. Next, an iron cylindrical pipe with an outer diameter of 10 mm was prepared as the core, and the nonwoven fabric was wound around the core several times to a predetermined thickness so that the outer diameter of the nonwoven fabric core was 12 mm, and the nonwoven fabric was placed in a furnace and heat-treated at an atmospheric temperature of 150°C for 1 hour, and then naturally cooled. After removing the core, the nonwoven fabric was cut to a length of 30 mm with a cutter to obtain a nonwoven fabric core. The resulting nonwoven core had an inner diameter of 10 mm, an outer diameter of 12 mm, and an apparent density of 0.35 g / cm. 3 It was.

[0083] 3. Manufacturing of laminated activated carbon molded bodies The raw materials prepared above were dispersed in water so that the mass ratio of each raw material in the activated carbon molded body was as shown in Table 1, to obtain a slurry. The nonwoven fabric core prepared was set in the core 2 of the molded form 1 shown in FIG. 11, and the molded form was immersed in the slurry. Then, the slurry was filtered while being sucked from the filtrate outlet 5 through the small suction hole 3 using a suction pump, so that the slurry was attached to the surface of the nonwoven fabric core, and a slurry molded body in which the nonwoven fabric core and the activated carbon layer (the layer that becomes the activated carbon molded body) were integrated was obtained. The obtained slurry molded body was pulled out of the molded form, and the slurry molded body was dried in a drying furnace at 120° C. for 15 hours to obtain a cylindrical laminated activated carbon molded body (a laminate of a nonwoven fabric core and an activated carbon molded body) with an outer diameter of 40 mm, an inner diameter of 12 mm, and a length of 30 mm. The mass of the obtained activated carbon molded body was 15.0 g, and the mass of the activated carbon contained in the activated carbon molded body was 13.8 g.

[0084] <Comparative Example 1> 1. Preparation of raw materials for activated carbon molding In producing the activated carbon molded body, the following raw materials were prepared. Fibrous activated carbon D (manufactured by A-DOLL Co., Ltd., product name "A-7") Granular activated carbon E (product name "FM-150" manufactured by Cataler Co., Ltd.) -Heat-fusible staple fiber (heat-fusible staple fiber with polyethylene terephthalate copolymerized with isophthalic acid as a heat-fusible component in the sheath and polyethylene terephthalate in the core; the sheath has a melting point of 110°C, the core has a melting point of 260°C, the fiber length is 51mm, the fiber diameter is 12μm, and the fineness is 2.2dtex) Pulp (product name: Vipal (registered trademark), manufactured by Nippon Exlan Kogyo Co., Ltd., fibrillated acrylic fiber, freeness: 50 ml)

[0085] 2. Manufacturing of nonwoven fabric that will become activated carbon molded bodies The above prepared raw materials were mixed using a pulper so that the mass ratio of each raw material in the activated carbon molded body was as shown in Table 1, and a uniformly dispersed slurry was prepared. The obtained slurry was poured onto a wire at a predetermined flow rate and dehydrated to adjust the basis weight. After that, the sheet was dried in a dryer part through a press part, and the sheet surface was smoothed in a calendar part before being wound on a reel. The sheet was then hot-pressed at 110°C with a hot press roller to obtain a wet nonwoven fabric containing activated carbon.

[0086] 3. Manufacturing of activated carbon molded bodies A cylindrical iron pipe with an outer diameter of 10 mm was prepared as a core, and the wet nonwoven fabric containing the activated carbon was wound around the core several times to a predetermined thickness. The wet nonwoven fabric was then placed in a furnace in a wound state, heat-treated at an atmospheric temperature of 150°C for 2 hours, and then naturally cooled. The core was then removed, and the nonwoven fabric was cut to a length of 60 mm with a cutter to obtain an activated carbon molded body. The height (length) of the obtained activated carbon molded body was 60 mm, the outer diameter was 30 mm, the inner diameter was 10 mm, the mass was 13.8 g, and the mass of the activated carbon contained in the activated carbon molded body was 10.5 g.

[0087] <Comparative Example 2> 1. Preparation of raw materials for activated carbon molding In producing the activated carbon molded body, the following raw materials were prepared. Fibrous activated carbon B (manufactured by A-DOLL Co., Ltd., product name "A-15") -Heat-fusible staple fiber (a heat-fusible staple fiber in which polyethylene terephthalate copolymerized with isophthalic acid as a heat-fusible component is arranged in the sheath and polyethylene terephthalate in the core. The melting point of the sheath is 110°C, the melting point of the core is 260°C, the fiber length is 51 mm, the fiber diameter is 12 μm, and the fineness is 2.2 dtex)

[0088] 2. Manufacturing of nonwoven fabric for use as activated carbon molding Each of the raw materials prepared above was carded to form a thin web, which was then needle-punched, heat-treated at a temperature of 163° C., and cooled to obtain a needle-punched nonwoven fabric.

[0089] 3. Manufacturing of activated carbon molded bodies A cylindrical iron pipe with an outer diameter of 10 mm was prepared as a core, and the needle-punched nonwoven fabric containing the activated carbon was wound around the core several times to a predetermined thickness. The wound needle-punched nonwoven fabric was then placed in a furnace and heat-treated at an atmospheric temperature of 150°C for 2 hours, and then naturally cooled. The core was then removed, and the fabric was cut to a length of 60 mm with a cutter to obtain an activated carbon molded body. The height (length) of the obtained activated carbon molded body was 60 mm, the outer diameter was 33 mm, the inner diameter was 10 mm, the mass was 9.6 g, and the mass of the activated carbon contained in the activated carbon molded body was 7.9 g.

[0090] <Measurement of physical properties> 1. Pore volume and specific surface area of ​​activated carbon molded bodies A measurement sample was taken from the center of the length direction of the obtained activated carbon molded body so that the mass was 0.1 g. The measurement sample was measured from the nitrogen adsorption isotherm at 77 K using Quantachrome's "AUTOSORB-6". The specific surface area was calculated from the measurement point at a relative pressure of 0.1 by the BET method. The total pore volume and the pore volume in each pore diameter range listed in Table 1 were analyzed by calculating the pore volume distribution by applying N2at 77K on carbon [slit pore, QSDFT equilibrium model] as a calculation model to the measured nitrogen desorption isotherm. Specifically, the pore volume in each pore diameter range listed in Table 1 is the read value of the graph showing the cumulative pore volume distribution shown in Figures 6 to 10 or a value calculated from the read value. More specifically, the pore volume of a pore diameter of 0.65 nm or less is the read value of the cumulative pore volume (cc / g) at the horizontal axis Pore Width of 0.65 nm in the cumulative pore volume distribution diagram. Similarly, the pore volume of a pore diameter of 0.8 nm or less, the pore volume of a pore diameter of 1.0 nm or less, the pore volume of a pore diameter of 1.3 nm or less, the pore volume of a pore diameter of 1.5 nm or less, the pore volume of a pore diameter of 2.0 nm or less, the pore volume of a pore diameter of 2.5 nm or less, the pore volume of a pore diameter of 3.0 nm or less, the pore volume of a pore diameter of 3.5 nm or less, the pore volume of a pore diameter of 4.0 nm or less, the pore volume of a pore diameter of 5.0 nm or less, and the pore volume of a pore diameter of 5.5 nm or less were obtained. The pore volume of a pore diameter of 2.0 nm or more was calculated by subtracting the pore volume of a pore diameter of 2.0 nm or less from the total pore volume obtained by the QSDFT method. The pore volume in the range of pore diameters of 2.0 nm to 2.5 nm was calculated by subtracting the pore volume of a pore diameter of 2.0 nm or less from the pore volume of a pore diameter of 2.5 nm or less. The pore volume of the pores having a diameter of 2.5 nm or more and 3.0 nm or less was calculated by subtracting the pore volume of the pores having a diameter of 2.5 nm or less from the pore volume of the pores having a diameter of 3.0 nm or less. The pore volume of the pores having a diameter of 3.0 nm or more and 3.5 nm or less was calculated by subtracting the pore volume of the pores having a diameter of 3.0 nm or less from the pore volume of the pores having a diameter of 3.5 nm or less.The pore volume in the pore diameter range of 3.5 nm to 4.0 nm was calculated by subtracting the pore volume of 3.5 nm or less from the pore volume of 4.0 nm or less. The pore volume in the pore diameter range of 4.0 nm to 4.5 nm was calculated by subtracting the pore volume of 4.0 nm or less from the pore volume of 4.5 nm or less. The pore volume in the pore diameter range of 4.0 nm or more was calculated by subtracting the pore volume of 4.0 nm or less from the total pore volume obtained by the QSDFT method. The pore volume in the pore diameter range of 0.65 nm to 0.8 nm was calculated by subtracting the pore volume of 0.65 nm or less from the pore volume of 0.8 nm or less. The pore volume in the range of pore diameters of 0.8 nm to 1.0 nm was calculated by subtracting the pore volume of pore diameters of 0.8 nm or less from the pore volume of pore diameters of 1.0 nm or less. The pore volume in the range of pore diameters of 1.0 nm to 1.5 nm was calculated by subtracting the pore volume of pore diameters of 1.0 nm or less from the pore volume of pore diameters of 1.5 nm or less. The pore volume in the range of pore diameters of 1.3 nm to 1.5 nm was calculated by subtracting the pore volume of pore diameters of 1.3 nm or less from the pore volume of pore diameters of 1.5 nm or less. The pore volume in the range of pore diameters of 1.5 nm to 2.0 nm was calculated by subtracting the pore volume of pore diameters of 1.5 nm or less from the pore volume of pore diameters of 2.0 nm or less.

[0091] 2. The filter's ability to remove fluorine-containing organic compounds (1) Measurements based on NSF / ANSI 53-2021 (DRINKING WATER TREATMENT UNITS-HEALTH EFFECTS, a standard established by NSF International, based in Michigan, USA) First, the filter was loaded into a stainless steel housing. Next, perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) were added to tap water with a total organic matter concentration (TOC) (concentration of organic matter converted to carbon (C) measured by a TOC meter (TOC-5000 manufactured by Shimadzu Corporation) of 0.5 mg / L or less using a commercially available activated carbon filter and hollow fiber membrane, so that the concentration of PFOA was 0.0005 ± 0.00005 mg / L and the concentration of PFOS was 0.001 ± 0.00010 mg / L (pH = 7.5 ± 0.5, temperature 20 ± 2.5 ° C, sulfate ion 200 ± 40 mg / L, chloride ion 100 ± 20 mg / L, alkalinity 200 ± 40 mg / L, turbidity less than 1 NTU) to prepare conditioned raw water. The adjusted raw water was continuously passed through the filter loaded in the stainless steel housing at a filtration flow rate of 2 L / min. The concentrations of PFOS and PFOA before and after passing through the filter were quantitatively measured by solid-phase extraction liquid chromatography mass spectrometry (measurements were performed based on the Ministry of Health, Labor and Welfare's "Testing Methods for Water Quality Management Target Setting Items (Notice of Water Quality Control No. 1010001 dated October 10, 2003), Target 31 Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA)"). The point at which the total water concentration of PFOS and PFOA in the effluent water (water that passed through the filter) reached 0.00007 mg / L or more was defined as the breakthrough point, and the total amount of filtered water (L) up to the breakthrough point was calculated. The obtained total amount of filtered water (L) was multiplied by the volume (cm) of the activated carbon molded body constituting the filter. 3 ) is the value divided by 1 cm of the activated carbon molding that constitutes the filter. 3 Filtration volume per unit (L / cm 3 The total amount of filtrate (L) was divided by the total weight of the activated carbon contained in the activated carbon molded body constituting the filter to obtain the amount of filtrate per gram of activated carbon contained in the activated carbon molded body constituting the filter (L / g). In the measurement of the removal performance of fluorine-containing organic compounds, the superficial velocity was 3183 h -1 , Example 2 is 3609h -1 , Example 3 is 3498h -1 , Comparative Example 1 is 3183h -1 , Comparative Example 2 is 2574h -1 It was.

[0092] (2) Measurements based on NSF / ANSI 53-2022 (DRINKING WATER TREATMENT UNITS-HEALTH EFFECTS, a standard established by NSF International, based in Michigan, USA) First, the filter was loaded into a stainless steel housing. Next, perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) were added to tap water with a total organic matter concentration (TOC) (concentration of organic matter converted to carbon (C) measured by a TOC meter (TOC-5000 manufactured by Shimadzu Corporation) of 0.5 mg / L or less using a commercially available activated carbon filter and hollow fiber membrane, so that the concentration of PFOA was 0.0005 ± 0.00005 mg / L and the concentration of PFOS was 0.001 ± 0.00010 mg / L (pH = 7.5 ± 0.5, temperature 20 ± 2.5 ° C, sulfate ion 200 ± 40 mg / L, chloride ion 100 ± 20 mg / L, alkalinity 200 ± 40 mg / L, turbidity less than 1 NTU) to prepare conditioned raw water. The adjusted raw water was continuously passed through the filter loaded in the stainless steel housing at a filtration flow rate of 2 L / min. The concentrations of PFOS and PFOA before and after passing through the filter were quantitatively measured by solid-phase extraction liquid chromatography mass spectrometry (measurements were performed based on the Ministry of Health, Labor and Welfare's "Testing Methods for Water Quality Management Target Setting Items (Notice of Water Quality Control No. 1010001 dated October 10, 2003), Target 31 Perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA)"). The point at which the total water concentration of PFOS and PFOA in the effluent water (water that passed through the filter) reached 0.00002 mg / L or more was defined as the breakthrough point, and the total amount of filtered water (L) up to the breakthrough point was calculated. The obtained total amount of filtered water (L) was multiplied by the volume (cm) of the activated carbon molded body constituting the filter. 3 ) is the value divided by 1 cm of the activated carbon molding that constitutes the filter. 3 Filtration volume per unit (L / cm 3 The total amount of filtered water (L) obtained was divided by the total weight of activated carbon contained in the activated carbon molded body constituting the filter, and the value was defined as the amount of filtered water per 1 g of activated carbon contained in the activated carbon molded body constituting the filter (L / g).

[0093] The physical properties of the obtained filter are shown in Table 1. In addition, Figs. 1 to 5 show log differential pore volume distribution diagrams calculated by the QSDFT method for the activated carbon molded bodies constituting the filters of Examples 1 to 3 and Comparative Examples 1 and 2. The log differential pore volume distribution (dV / dlogD) is obtained by dividing the differential pore volume dV by the logarithmic difference value dlogD of the pore diameter, and plotting this against the pore diameter. Figs. 6 to 10 show cumulative pore volume distribution diagrams calculated by the QSDFT method for the activated carbon molded bodies constituting the filters of Examples 1 to 3 and Comparative Examples 1 and 2.

[0094] [Table 1]

[0095] As is clear from Table 1, the filters of Examples 1 to 3 are filters containing activated carbon molded bodies containing activated carbon, and the activated carbon molded bodies have a pore volume A (cc / g) of pores with diameters of 2.0 nm or less that is 0.30 cc / g or more, and a pore volume B (cc / g) of pores with diameters in the range of pores 3.0 to 3.5 nm that is 0.01 cc / g or more, among the pore volumes calculated by the QSDFT method. Therefore, even when the superficial velocity (SV) of the water to be treated is high, the filters had excellent performance for removing fluorine-containing organic compounds.

[0096] On the other hand, in Comparative Example 1, the pore volume of the activated carbon molded body calculated by the QSDFT method was such that the pore volume A (cc / g) of pores with diameters of 2.0 nm or less was less than 0.3 cc / g, and the pore volume B (cc / g) of pores with diameters in the range of 3.0 to 3.5 nm was less than 0.01 cc / g, and therefore the removal performance of fluorine-containing organic compounds was poor when the superficial velocity (SV) of the water to be treated was high.

[0097] In addition, in Comparative Example 2, the activated carbon molded body had a pore volume B (cc / g) of pores with diameters in the range of 3.0 to 3.5 nm, which was calculated by the QSDFT method, of less than 0.01 cc / g, and therefore had poor removal performance for fluorine-containing organic compounds when the superficial velocity (SV) of the water to be treated was high. [Explanation of symbols]

[0098] 1: Molding formwork 2: Core body 3: Small hole for suction 4, 4': Flange 5:Filtrate outlet

Claims

1. A filter including an activated carbon molded body, The activated carbon molded body is a filter in which, among the pore volumes calculated by the QSDFT method, the pore volume A (cc / g) of pores with a pore diameter of 2.0 nm or less is 0.30 cc / g or more, the pore volume B (cc / g) of pores with a pore diameter in the range of 3.0 to 3.5 nm is 0.01 cc / g or more, and the pore volume (cc / g) of pores with a pore diameter of 1.0 nm or less is 0.15 cc / g or more and 0.285 cc / g or less.

2. A filter comprising an activated carbon molded body, The activated carbon molded body is a filter in which, among the pore volumes calculated by the QSDFT method, the pore volume A (cc / g) of pores with a pore diameter of 2.0 nm or less is 0.30 cc / g or more, the pore volume B (cc / g) of pores with a pore diameter in the range of 3.0 to 3.5 nm is 0.01 cc / g or more, and the pore volume (cc / g) of pores with a pore diameter of 4.0 nm or more is 0.05 cc / g or more and 0.13 cc / g or less.

3. The activated carbon molded body is a filter as described in claim 1 or 2, wherein the pore volume (cc / g) of pores with a diameter of 1.0 nm or less, calculated by the QSDFT method, is 0.15 cc / g or more and 0.23 cc / g or less.

4. The filter described in claim 1, wherein the pore volume (cc / g) of the activated carbon molded body having a pore diameter of 4.0 nm or more is 0.05 cc / g or more and 0.13 cc / g or less, among the pore volume calculated by the QSDFT method.

5. The activated carbon molded body is a filter as described in claim 1 or 2, wherein the pore volume (cc / g) of pores with diameters of 0.65 nm or less calculated by the QSDFT method is 0.015 cc / g or more and 0.07 cc / g or less.

6. The activated carbon molded body is a filter as described in claim 1 or 2, wherein the pore volume (cc / g) of pores with diameters in the range of 1.0 to 1.5 nm calculated by the QSDFT method is 0.106 cc / g or more and 0.20 cc / g or less.

7. The activated carbon molded body 1 cm 2 measured by the following method 3 The amount of filtered water per unit is 15 L / cm 3 The filter according to claim 1 or 2, wherein <Measurement method> The measurement is performed according to the following method in accordance with NSF / ANSI 53-2021 (DRINKING WATER TREATMENT UNITS-HEALTH EFFECTS, a standard by NSF International based in Michigan, USA). The filter is loaded into a stainless steel housing. The tap water is adjusted to a total organic matter concentration (TOC) of 0.5 mg / L or less (concentration of organic matter converted to carbon (C) measured by a TOC meter) using an activated carbon filter and a hollow fiber membrane, and perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) are added to the tap water so that the PFOA concentration is 0.0005±0.00005 mg / L and the PFOS concentration is 0.001±0.00010 mg / L (pH=7.5±0.5, temperature 20±2.5°C, sulfate ion 200±40 mg / L, chloride ion 100±20 mg / L, alkalinity 200±40 mg / L, turbidity less than 1 NTU). The adjusted raw water is continuously passed through the filter loaded in the stainless steel housing at a filtration flow rate of 2 L / min, and the concentrations of PFOS and PFOA before and after passing through the filter are quantitatively measured by solid-phase extraction liquid chromatography mass spectrometry. The point at which the total water concentration of PFOS and PFOA in the effluent water becomes 0.00007 mg / L or more is set as the breakthrough point, and the total amount of filtered water (L) up to the breakthrough point is calculated. The obtained total amount of filtered water (L) is multiplied by the volume (cm) of the activated carbon molded body constituting the filter. 3 ) is divided by 1 cm of the activated carbon molding that constitutes the filter. 3 Filtration volume per unit (L / cm 3 )

8. 3. The filter according to claim 1, which is used for removing fluorine-containing organic compounds from water to be treated.

9. A method for removing fluorine-containing organic compounds, comprising the step of passing treated water containing fluorine-containing organic compounds through a filter described in claim 1 or 2, thereby removing the fluorine-containing organic compounds in the treated water.