Carbonaceous material, method for producing the same, and method for adsorbing palladium complexes

Abstract

To provide a carbonaceous material with high performance of adsorbing various palladium complexes.SOLUTION: A carbonaceous material according to the present invention has a ratio of mesopores from 6.4% to 50.0% inclusive, a reactive black 5 value from 1.0 g / L to 8.0 g / L inclusive, and an iodine adsorption amount from 1,000 mg / g to 1,600 mg / g inclusive.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a carbonaceous material, a method for producing the same, and a method for adsorbing a palladium complex.

Background Art

[0002] In organic synthetic chemistry, homogeneous catalysts containing palladium are widely used for the purpose of promoting reactions such as carbon-carbon bond formation and asymmetric hydrogenation. By dissolving these palladium catalysts in a solution, the reaction can be efficiently promoted. After the reaction is completed, the palladium catalyst can be removed by crystallization and distillation, etc. However, when the product is used in electronic materials and pharmaceuticals, etc., it is necessary to remove the palladium catalyst in the product and sufficiently reduce its content.

[0003] As a method for removing a palladium catalyst, for example, in Patent Document 1, a method of treating a solution after an organic reaction with activated alumina having a specific surface area of 50 m 2 / g or more and 400 m 2 / g or less is presented.

[0004] In Patent Document 2, as a method for reducing residual palladium in a pharmaceutical active ingredient, a method for reducing residual palladium is described in which a 3-substituted phosphine is added to a mixed solution of a pharmaceutical active ingredient, a solubilizing agent, and water, and further, a poor solvent is added to crystallize the pharmaceutical active ingredient.

[0005] In Patent Document 3, an adsorbent used for removing metal components such as a palladium catalyst dissolved in an organic solvent, having a specific surface area of 1300 m 2 / g or more and an average pore diameter of 1.8 nm or more, is described.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007] However, in the removal method described in Patent Document 1, the solution for removing the palladium catalyst is an organic reaction solution using a catalyst containing a phosphorus ligand and a palladium compound. Therefore, it is not sufficiently effective for catalysts that do not contain a phosphorus ligand, such as palladium acetate.

[0008] In the reduction method described in Patent Document 2, a trisubstituted phosphine that forms a complex with residual palladium is added to the solution to remove the complex of the trisubstituted phosphine and the residual palladium. However, in the method described in Patent Document 2, it is difficult to remove palladium that is difficult to undergo ligand exchange with trisubstituted phosphine, such as a palladium complex having a multidentate ligand. In addition, as a result of the trisubstituted phosphine remaining, there is also a concern that the target product will be contaminated.

[0009] Patent Document 3 describes a method of adsorbing a palladium catalyst with activated carbon, and states that high removal performance is exhibited by setting the pore characteristics and the amount of surface functional groups of the adsorbent within a specific range for palladium acetate, which is a divalent palladium complex. However, Patent Document 3 does not show the effectiveness for zero-valent palladium complexes, and it is difficult to say that the activated carbon described in Patent Document 3 can be applied to the removal of various palladium complexes such as palladium catalysts.

[0010] The present invention has been made in view of such problems, and an object thereof is to provide a carbonaceous material having high adsorption performance for various palladium complexes, a method for producing the same, and a method for adsorbing a palladium complex. [Means for Solving the Problems]

[0011] As a result of intensive research to solve the above problems, the inventors of the present invention have found that a carbonaceous material in which the proportion of mesopores, reactive black 5 valence, and iodine adsorption amount are each in a specific range has high adsorption performance for various palladium complexes, and thus have completed the present invention.

[0012] The present invention includes the following embodiments. [1] A carbonaceous material in which the proportion of mesopores is 6.4% or more and 50.0% or less, the reactive black 5 valence is 1.0 g / L or more and 8.0 g / L or less, and the iodine adsorption amount is 1,000 mg / g or more and 1,600 mg / g or less.

[0013] [2] The carbonaceous material according to [1], wherein the pore volume of mesopores determined by the BJH method from the N adsorption isotherm at -196 °C is 0.16 cm / g or more and 0.60 cm / g or less. 2 / g or more and 0.60 cm 3 / g or less. 3

[0014] [3] The carbonaceous material according to [1], wherein the specific surface area determined by the BET method from the N adsorption isotherm at -196 °C is 950 m / g or more and 1,700 m / g or less. 2 / g or more and 1,700 m 2 / g or less. 2

[0015] [4] The carbonaceous material according to [1], wherein the specific surface area determined by the BJH method from the N adsorption isotherm at -196 °C is 23 m / g or more and 500 m / g or less. 2 / g or more and 500 m 2 / g or less. 2

[0016] [5] The carbonaceous material according to [1], wherein the pH is 4.5 or more and 9.5 or less.

[0017] [6] The carbonaceous material according to [1], wherein the packing density measured by the tapping method is 0.20 g / mL or more and 0.55 g / mL or less.

[0018] [7] The carbonaceous material according to any one of [1] to [6], which is used for the adsorption of a zero-valent palladium complex and / or a divalent palladium complex in an organic solvent.

[0019] [8] A method for producing a carbonaceous material according to any one of [1] to [6], comprising a carbonization step of carbonizing a raw material to obtain a carbide, and an activation step of subjecting the carbide to an activation treatment to obtain an activated product.

[0020] [9] The production method according to [8], further comprising a washing step of washing the activated product.

[0021]

[10] The production method according to [8], wherein the raw material is at least one selected from the group consisting of coconut shells and wood powder.

[0022]

[11] An adsorption method of a palladium complex, comprising an adsorption step of adsorbing a palladium complex onto the carbonaceous material according to any one of [1] to [6]. [Advantages of the Invention]

[0023] According to the present invention, it is possible to provide a carbonaceous material having high adsorption performance for various palladium complexes, a production method thereof, and an adsorption method of a palladium complex. [Brief Description of the Drawings]

[0024]

Figure 1

Figure 2

[0025] Hereinafter, embodiments for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the following present embodiment is an exemplification for explaining the present invention, and the present invention is not limited only to the present embodiment.

[0026] [Carbonaceous material] The carbonaceous material of this embodiment has a mesopore ratio of 6.4% or more and 50.0% or less, a reactive black pentavalent of 1.0 g / L or more and 8.0 g / L or less, and an iodine adsorption amount of 1,000 mg / g or more and 1,600 mg / g or less.

[0027] By having such requirements, the carbonaceous material has high adsorption performance for various palladium complexes such as palladium catalysts. Therefore, by using the carbonaceous material of this embodiment, it is possible to suitably remove palladium complexes in various applications.

[0028] The ratio of mesopores in the carbonaceous material is 6.4% or more and 50.0% or less. When the ratio of mesopores is within the above range, the carbonaceous material exhibits high adsorption performance for palladium complexes. When the ratio of mesopores is 6.4% or more, the carbonaceous material has a larger proportion of pores effective for palladium complexes with a large molecular size, and the adsorption performance is significantly improved. When the ratio of mesopores is 50.0% or less, the pore diameter of the carbonaceous material does not become too large, and it becomes easy to control the pores that adsorb palladium complexes.

[0029] In this specification, the pores of the carbonaceous material conform to the classification criteria of IUPAC (International Union of Pure and Applied Chemistry). According to the pore diameter (diameter), pores with a pore diameter of less than 2.0 nm are classified as micropores, pores with a pore diameter of 2.0 nm or more and 50.0 nm or less are classified as mesopores, and pores with a pore diameter exceeding 50.0 nm are classified as macropores. Mesopores are larger pores than micropores and are effective for the adsorption of palladium complexes with a large molecular size.

[0030] In this specification, the ratio of mesopores means, in the carbonaceous material, the specific surface area determined by the BET method from the N 2 adsorption isotherm at -196 °C (hereinafter, also simply referred to as "BET specific surface area"), and the N 2It is determined by the ratio of the specific surface area obtained by the BJH method from the adsorption isotherm (hereinafter, also simply referred to as "BJH specific surface area"). Mesopores are relatively large pores among the pores contributing to adsorption in the carbonaceous material. That is, the larger the proportion of mesopores, the better the adsorption performance of palladium complexes with large molecular sizes. For the specific measurement and calculation method of the proportion of mesopores, refer to the examples.

[0031] Since it has higher adsorption performance for various palladium complexes, the proportion of mesopores is preferably 10.0% or more and 40.0% or less, and more preferably 15.0% or more and 35.0% or less.

[0032] The reactive black 5 valence of the carbonaceous material is 1.0 g / L or more and 8.0 g / L or less. Reactive black 5 is a dye represented by the following formula (1) and is also referred to as C.I. Reactive Black-5.

[0033]

Chemical formula

[0034] Since reactive black 5 has a large molecular weight of 995.88 and a bulky structure, the reactive black 5 valence serves as an index for the adsorption characteristics of palladium complexes with large molecular sizes. When the reactive black 5 valence of the carbonaceous material is within the above range, the carbonaceous material exhibits high adsorption performance for various palladium complexes. When the reactive black 5 valence is 1.0 g / L or more, the carbonaceous material can ensure an appropriate pore volume for adsorbing palladium complexes with large molecular sizes while sufficiently maintaining an effective pore volume for palladium complexes with small molecular sizes, thus significantly improving the adsorption performance. When the reactive black 5 valence is 8.0 g / L or less, the carbonaceous material can sufficiently maintain an effective pore volume for palladium complexes with large molecular sizes. Therefore, a carbonaceous material having high adsorption performance particularly for palladium complexes with large molecular sizes can be obtained.

[0035] Reactive Black 5 value can be calculated as follows. That is, first, using an ultraviolet-visible spectrophotometer, under the conditions of a wavelength of 594 nm and an optical path length (cell length) of 10 mm, for a test solution containing Reactive Black 5, after mixing a carbonaceous material with the test solution and sufficiently adsorbing Reactive Black 5 onto the carbonaceous material, measure the absorbance of each of the residual solutions obtained by removing the carbonaceous material adsorbed with Reactive Black 5. Then, using these absorbances, calculate the residual rate (%) of Reactive Black 5 contained in the residual solution and the adsorption amount ( / g) of Reactive Black 5 per 1 g of the carbonaceous material. The Reactive Black 5 value (g / L) is calculated as the amount of the carbonaceous material required to remove 99% of Reactive Black 5 in 1 L of the test solution using these values. In the measurement of the Reactive Black 5 value, as the carbonaceous material, it is preferable to use a carbonaceous material whose 50% particle size (D50) in terms of volume-based cumulative distribution is adjusted to be 9.0 μm or more and 11.0 μm or less. In this specification, the 50% particle size (D50) refers to the value measured as the volume-based median diameter using a laser diffraction light scattering method particle size distribution measuring device. For the specific measurement and calculation method of the Reactive Black 5 value, reference may be made to the examples.

[0036] Since it has higher adsorption performance for various palladium complexes, the Reactive Black 5 value is preferably 1.3 g / L or more and 7.0 g / L or less, more preferably 1.5 g / L or more and 5.0 g / L or less, still more preferably 1.6 g / L or more and 4.0 g / L or less, and even more preferably 1.7 g / L or more and 2.3 g / L or less.

[0037] The iodine adsorption amount of the carbonaceous material is 1,000 mg / g or more and 1,600 mg / g or less. The iodine adsorption amount is an index of the surface area of pores in the carbonaceous material that can physically adsorb palladium complexes. When the iodine adsorption amount of the carbonaceous material is within the above range, the carbonaceous material exhibits high adsorption performance for palladium complexes. When the iodine adsorption amount is 1,000 mg / g or more, there is a sufficient surface area contributing to physical adsorption, and the adsorption performance for palladium complexes is significantly improved. When the iodine adsorption amount is 1,600 mg / g or less, the pores of the carbonaceous material do not become too large, and it becomes easier to control the pores that adsorb palladium complexes.

[0038] The iodine adsorption amount is measured and calculated in accordance with JIS K 1474 (2014). For the specific measurement and calculation method of the iodine adsorption amount, refer to the examples.

[0039] Since it has higher adsorption performance for various palladium complexes, the iodine adsorption amount is preferably 1,030 mg / g or more and 1,570 mg / g or less, more preferably 1,055 mg / g or more and 1,550 mg / g or less, and still more preferably 1,100 mg / g or more and 1,350 mg / g or less.

[0040] In the carbonaceous material, the pore volume of mesopores (hereinafter, also simply referred to as "pore volume of mesopores") obtained by the BJH method from the N adsorption isotherm at -196 °C 2 is preferably 0.16 cm 3 / g or more and 0.60 cm 3 / g or less. When the pore volume of mesopores is within the above range, the carbonaceous material tends to be able to realize the adsorption performance for various palladium complexes at a higher level. When the pore volume of mesopores is 0.16 cm 3 / g or more, the carbonaceous material can have many relatively large pores that are effective for the adsorption of palladium complexes. Therefore, the carbonaceous material tends to have high palladium adsorption performance. When the pore volume of mesopores is 0.60 cm 3By being below / g, the pores of the carbonaceous material do not become too large, and the carbonaceous material can have many pores effective for the adsorption of the palladium complex. Therefore, the carbonaceous material tends to have high palladium adsorption performance. For the specific measurement and calculation method of the pore volume of the mesopores, refer to the examples.

[0041] Since the adsorption performance for various palladium complexes tends to be realized at a higher level, the pore volume of the mesopores is preferably 0.20 cm 3 / g or more and 0.59 cm 3 / g or less, more preferably 0.26 cm 3 / g or more and 0.58 cm 3 / g or less, still more preferably 0.30 cm 3 / g or more and 0.57 cm 3 / g or less, even more preferably 0.35 cm 3 / g or more and 0.56 cm 3 / g or less.

[0042] In the carbonaceous material, the specific surface area (i.e., BET specific surface area) determined by the BET method from the adsorption isotherm of N at -196 °C is preferably 950 m 2 / g or more and 1,700 m 2 / g or less. The BET specific surface area is an index indicating the degree of progress of the activation of the carbonaceous material. By the BET specific surface area being in the above range, the adsorption performance for various palladium complexes tends to be realized at a higher level. By the BET specific surface area being 950 m 2 / g or more, the carbonaceous material has a sufficient surface area contributing to physical adsorption and tends to obtain high adsorption performance for the palladium complex. By the BET specific surface area being 1,700 m 2 / g or less, the pores of the carbonaceous material do not become too large, and the carbonaceous material tends to have many pores effective for the adsorption of the palladium complex. For the specific measurement and calculation method of the BET specific surface area, refer to the examples. 2 / g or less, the pores of the carbonaceous material do not become too large, and the carbonaceous material tends to have many pores effective for the adsorption of the palladium complex. For the specific measurement and calculation method of the BET specific surface area, refer to the examples.

[0043] Since there is a tendency to achieve a higher level of adsorption performance for various palladium complexes, the BET specific surface area is preferably 1,000 m 2 / g or more and 1,670 m 2 / g, more preferably 1,020 m 2 / g or more and 1,650 m 2 / g or less, and even more preferably 1,100 m 2 / g or more and 1,550 m 2 / g or less, and even more preferably 1330 m 2 / g or more and 1,500 m 2 / g or less.

[0044] In the carbonaceous material, the specific surface area (i.e., BJH specific surface area) determined by the BJH method from the N 2 adsorption isotherm at -196 °C is preferably 23 m 2 / g or more and 500 m 2 / g or less. The BJH specific surface area is an index indicating the abundance of mesopores in the carbonaceous material. When the BJH specific surface area is within the above range, the carbonaceous material tends to achieve a higher level of adsorption performance for various palladium complexes. When the BJH specific surface area is 23 m 2 / g or more, the carbonaceous material can have a large amount of surfaces of relatively large mesopores capable of physically adsorbing palladium complexes. Therefore, the carbonaceous material tends to have high palladium adsorption performance. When the BJH specific surface area is 500 m 2 / g or less, the pores of the carbonaceous material do not become too large, and the carbonaceous material can have a large amount of pore surfaces effective for the adsorption of palladium complexes. Therefore, the carbonaceous material tends to have high palladium adsorption performance. For the specific measurement and calculation method of the BJH specific surface area, reference may be made to the examples.

[0045] Since there is a tendency to achieve a higher level of adsorption performance for various palladium complexes, the BJH specific surface area is preferably 25 m 2 / g or more and 470 m 2 / g or less, more preferably 50 m 2 / g or more and 450 m 2It is below / g, more preferably 100 m 2 / g or more and 430 m 2 It is below / g, even more preferably 150 m 2 / g or more and 420 m 2 It is below / g, still more preferably 250 m 2 / g or more and 410 m 2 It is below / g.

[0046] In the carbonaceous material, the pH is preferably 4.5 or more and 9.5 or less. In the present embodiment, the pH is an index indicating the electrical properties of the carbonaceous material. When the pH is within the above range, the carbonaceous material tends to have less electrical bias on its surface. Therefore, the carbonaceous material is less likely to be affected by the electrical properties possessed by the palladium complex, and tends to be able to realize the adsorption performance for various palladium complexes at a higher level. The pH can be measured using a known pH meter, and for specific measurement and calculation methods, reference may be made to the examples.

[0047] The inventors of the present invention are not certain about the reason why the adsorption performance of the carbonaceous material is further improved according to the carbonaceous material having a pH within the above range, but presume as follows. That is, the fact that the pH is in the range of 4.5 or more and 9.5 or less means that when the carbonaceous material is immersed in water, the hydrogen ion concentration in the water is 10 -4.5 mol / L or more and 10 -9.5 mol / L or less. This indicates that, for example, even when the carbonaceous material has acid-dissociable groups on its surface, the amount of hydrogen ions released from the groups is sufficiently small. Also, for example, even when the carbonaceous material contains metal hydroxides adsorbed on its surface as impurities, the amount of hydroxide ions released from the metal hydroxides is sufficiently small.

[0048] Therefore, when the pH is in the range of 4.5 or more and 9.5 or less, the surface of the carbonaceous material is electrically almost neutral, and it can be said that the surface is in a more hydrophobic state. Therefore, the carbonaceous material has improved physical adsorption characteristics for electrically neutral substances. For example, its adsorption performance is also more excellent for electrically neutral palladium complexes such as bis(dibenzylideneacetone)palladium(0).

[0049] Also, when the pH is in the range of 4.5 or more and 9.5 or less, most of the acid-dissociable groups present on the surface of the carbonaceous material do not dissociate. Such groups can preferably react with relatively acidic metal ions such as palladium(II) ions, and while dissociating hydrogen ions, a bond between a metal and oxygen such as a Pd-O bond is formed. Therefore, the carbonaceous material also has excellent adsorption performance for relatively acidic palladium(II) complexes such as palladium acetate.

[0050] From the above, when the pH is in the range of 4.5 or more and 9.5 or less, the carbonaceous material has more excellent adsorption characteristics for both electrically neutral palladium complexes and relatively acidic palladium(II) complexes. Therefore, it is estimated that the carbonaceous material can achieve adsorption characteristics for various palladium complexes at a higher level. Examples of the acid-dissociable groups include, but are not limited to, hydroxyl groups and carboxyl groups.

[0051] Since there is a tendency to be able to realize the adsorption performance for various palladium complexes at an even higher level, the pH is preferably 5.0 or more and 9.0 or less, more preferably 5.5 or more and 8.5 or less, and still more preferably 6.0 or more and 8.0 or less.

[0052] In the carbonaceous material, the bulk density measured by the tapping method (hereinafter also simply referred to as "bulk density") is preferably 0.20 g / mL or more and 0.55 g / mL or less. The bulk density tends to be greatly affected by the pore volume of the carbonaceous material. Therefore, when the bulk density is measured using a carbonaceous material in which the 50% particle diameter (D50) of the cumulative distribution on a volume basis is adjusted to 9.0 μm or more and 11.0 μm or less, the value of the bulk density serves as an index of the pore volume possessed by the carbonaceous material. When the bulk density is within the above range, the carbonaceous material tends to achieve a higher level of adsorption performance for various palladium complexes. When the bulk density is 0.20 g / mL or more, pores contributing to physical adsorption tend to be sufficiently present. Therefore, the carbonaceous material tends to have higher adsorption performance for palladium complexes. When the bulk density is 0.55 g / mL or less, the pores of the carbonaceous material do not become too large, and it can hold many pores effective for the adsorption of palladium complexes. Therefore, the carbonaceous material tends to have high palladium adsorption performance. For the specific measurement and calculation method of the bulk density, reference may be made to the examples.

[0053] Since there is a tendency to be able to achieve a higher level of adsorption performance for various palladium complexes, the bulk density is preferably 0.25 g / mL or more and 0.50 g / mL or less.

[0054] The shape of the carbonaceous material varies depending on the use and is not particularly limited. Such shapes include, for example, powdery, massive, crushed, spherical, cylindrical, elliptical cylindrical, elliptical frustum, and rod-shaped such as triangular prism, quadrangular prism, pentagonal prism, and hexagonal prism, pellet-shaped such as solid pellet and hollow pellet, substrate-shaped (sheet-shaped), and block-shaped, etc.

[0055] The powdery carbonaceous material is used, for example, in batch processing and as a raw material for molded bodies. In this specification, "powdery" refers to, for example, fine powder, powder, fine granular, and granular powders, and usually, the 50% particle diameter (D50) of the cumulative distribution on a volume basis is 1 μm or more and 150 μm or less.

[0056] The crushed carbonaceous material is used, for example, in flow-through processing and columns for chromatography. In this specification, "crushed" refers to particles that do not have a fixed shape and usually have an arbitrary angular shape.

[0057] For example, when used in a column or the like, its shape is preferably cylindrical. In this specification, "cylindrical shape" does not necessarily mean a geometrically precise cylinder. The cross-sectional shape in a plane perpendicular to the central axis of the cylinder (hereinafter simply referred to as "cross-sectional shape") includes an oval shape, a circular shape, and an elliptical columnar shape, and also includes those in which the cylinder is somewhat curved or the surface of the cylinder has some irregularities. In this specification, for a circular or elliptical shape, for example, it means those in which the ratio of the major axis to the minor axis (major axis / minor axis) of the shape is 3 or less. As the cross-sectional shape, a circular shape and an elliptical shape are preferable because it is possible to fill the carbonaceous material in a column or the like with a higher density.

[0058] When the carbonaceous material is cylindrical, the length of the diameter of its cross-sectional shape varies depending on the application. For example, when used in a column or the like, it is usually about 1.0 mm or more and 10.0 mm or less. In this specification, "diameter" means the diameter of the circle when the cross-sectional shape is circular. On the other hand, when the cross-sectional shape is oval, oblong, or elliptical, "diameter" means the longest direction (i.e., the major axis direction) in those shapes. In this specification, "circular" includes an oval shape, a circular shape, and an elliptical shape in addition to a perfect circle.

[0059] When the carbonaceous material is cylindrical, the length in the longitudinal direction of the cylinder varies depending on the application. For example, when used in a column or the like, it is usually about 1.0 mm or more and 20.0 mm or less.

[0060] When the shape of the carbonaceous material is pellet-shaped, its planar shape can be, for example, a shape applicable to a column or the like. Such shapes include, for example, circular, elliptical, rectangular, rod-shaped, and distorted shapes in a planar view. When the shape of the carbonaceous material is pellet-shaped, its thickness is not particularly limited, and a known adsorbent applied to a column or the like can be referred to. The thickness is preferably such that it can be applied to a column or the like, and is usually 100 μm or more and 10,000 μm or less.

[0061] When the shape of the carbonaceous material is cylindrical pellet-shaped, the diameter of the pellet is preferably 2 mm or more and 10 mm or less, and the aspect ratio is preferably 1:1 to 1:10. Such pellets are suitable as adsorbents in columns or the like. In this specification, the aspect ratio means the ratio of the diameter to the height of one carbonaceous material, that is, the diameter of the carbonaceous material: the height of the carbonaceous material. The aspect ratio means the average value of the aspect ratios of 30 randomly selected carbonaceous materials.

[0062] The carbonaceous material is preferably activated carbon.

[0063] [Manufacturing method of carbonaceous material] The carbonaceous material of this embodiment can be obtained by a known manufacturing method.

[0064] Examples of such methods include a thermal decomposition method, an activation method, a coating method, and a vapor deposition method. As the manufacturing method, it is preferable to use the activation method. By using these manufacturing methods, a carbonaceous material having a mesopore ratio of 6.4% or more and 50.0% or less, a reactive black pentavalent of 1.0 g / L or more and 8.0 g / L or less, and an iodine adsorption amount of 1,000 mg / g or more and 1,600 mg / g or less can be more easily manufactured.

[0065] The manufacturing method of the carbonaceous material of this embodiment includes a carbonization step of carbonizing a raw material to obtain a carbide, and an activation step of subjecting the carbide to an activation treatment to obtain an activated product. The manufacturing method of the carbonaceous material of this embodiment preferably includes a washing step of washing the activated product.

[0066] (Carbonization step) The manufacturing method of the carbonaceous material includes a carbonization step of carbonizing a raw material to obtain a carbide. The raw material is not particularly limited as long as it can obtain a desired carbonaceous material. Examples of the raw material include plant-based raw materials or fossil-based raw materials such as wood, wood powder, fruit shells such as coconut shells, palm kernels, seeds such as ume and peach, by-products during pulp production, bagasse, molasses, coal (such as peat, lignite, brown coal, and bituminous coal), anthracite, petroleum distillation residue components, petroleum pitch, coke, and coal tar; various synthetic resins such as phenolic resin, vinyl chloride resin, vinyl acetate resin, melamine resin, urea resin, resorcinol resin, celluloid, epoxy resin, polyurethane resin, polyester resin, acrylic resin, and polyamide resin; synthetic rubbers such as polybutylene, polybutadiene, and polychloroprene; other synthetic woods; synthetic pulp, etc. These raw materials can be used alone or, depending on the required specifications, two or more kinds can be mixed and used in any ratio.

[0067] The raw material is preferably a natural product, and more preferably at least one selected from the group consisting of coconut shells and wood powder. By using such a raw material, a carbonaceous material with a mesopore ratio of 6.4% or more and 50.0% or less, a reactive black pentavalent of 1.0 g / L or more and 8.0 g / L or less, and an iodine adsorption amount of 1,000 mg / g or more and 1,600 mg / g or less can be more easily manufactured.

[0068] The raw material may contain additives, etc. as required. Also, additives, etc. may be added to the carbide as required. Examples of such additives include water, coal tar, tar anhydride, hard pitch, coal tar pitch, and petroleum pitch. The additives may be used alone or in combination of two or more. The additives are each usually blended in an amount of 1.0 to 50.0 parts by mass, preferably 1.0 to 30.0 parts by mass, per 100 parts by mass of the raw material or carbide. The total amount of the additives is usually 1 to 100 parts by mass, preferably 1 to 50 parts by mass, per 100 parts by mass of the raw material or carbide. When mixing the raw material or carbide with the additive, the oxygen content in the raw material or carbide may be adjusted in advance within the range of 1.0 to 20.0% by mass, preferably 1.0 to 10.0% by mass, based on 100% by mass of the raw material or carbide, if necessary. The adjustment of the oxygen content can be carried out, for example, by mixing the raw material or carbide with oxygen under heating at 150°C or higher and 300°C or lower.

[0069] In the method for producing the carbonaceous material, the raw material may be pulverized or molded before carbonization. Examples of such methods include a method in which the raw material is pulverized into a powder using a known pulverizer and then carbonized, and a method in which the raw material is molded into pellets by a known method and then carbonized, before carbonizing the raw material.

[0070] When the shape of the raw material is powder, the particle size (50% particle diameter of the cumulative distribution based on volume, D50) of the powder is preferably 1 μm or more and 150 μm or less.

[0071] The carbonization method of the raw material is not particularly limited, and examples thereof include a method of heating to 300°C or higher and 900°C or lower, preferably 400°C or higher and 800°C or lower, under oxygen-free conditions.

[0072] The carbonization time can be appropriately set according to the raw material and the equipment for carbonization. The carbonization time is, for example, 15 minutes or more and 20 hours or less, preferably 30 minutes or more and 10 hours or less. The carbonization treatment can be carried out using a known production equipment such as a rotary kiln. The carbonization treatment may also be carried out under reduced pressure by excluding air or in a nitrogen atmosphere.

[0073] In the method for producing a carbonaceous material, a carbide may be pulverized into a powder using a known pulverizer. Thereby, there is a tendency to more easily produce a carbonaceous material having a mesopore ratio of 6.4% or more and 50.0% or less, a reactive black pentavalent of 1.0 g / L or more and 8.0 g / L or less, and an iodine adsorption amount of 1,000 mg / g or more and 1,600 mg / g or less. In the method for producing a carbonaceous material, after pulverizing the carbide into a powder, an additive or the like may be added to the powdered carbide as necessary and kneaded by a known method, and the obtained kneaded product may be molded by a known method.

[0074] When the shape of the carbide is powder, the particle size of the carbide (50% particle diameter of the cumulative distribution based on volume, D50) is preferably 1 μm or more and 150 μm or less.

[0075] In the method for producing a carbonaceous material, a carbide, a powdered carbide, a kneaded product, or a powdered kneaded product may be molded into a cylindrical pellet shape using a known method. Thereby, there is a tendency to more easily produce a carbonaceous material having a mesopore ratio of 6.4% or more and 50.0% or less, a reactive black pentavalent of 1.0 g / L or more and 8.0 g / L or less, and an iodine adsorption amount of 1,000 mg / g or more and 1,600 mg / g or less. When the shape of the carbide is cylindrical pellet, the diameter of the cylindrical pellet is preferably 0.1 mm or more and 4.0 mm or less. Also, the aspect ratio (diameter: height) of the cylindrical pellet is preferably 1:1 to 1:10.

[0076] By the above carbonization step, a raw material carbide is obtained.

[0077] The method for producing a carbonaceous material may have a washing step and / or a drying step of performing a washing treatment and / or a drying treatment on the carbide after the carbonization step. The conditions in these steps are not particularly limited, and known conditions can be adopted. Also, the following washing step and drying step may be referred to.

[0078] (Activation step) The method for producing the carbonaceous material includes an activation step of subjecting a carbide to an activation treatment to obtain an activated product.

[0079] As the activation treatment, a known method can be adopted. Examples of such a method include an activation method using an active gas such as water vapor, oxygen, and carbon dioxide. For the activation treatment, known production equipment such as a rotary kiln, a fluidized furnace, and a sleep furnace (vertical furnace) can be used. Further, the activation treatment may be performed under reduced pressure by excluding air, or may be performed in a nitrogen atmosphere. As the activation treatment, for example, when water vapor is used, a method of bringing water vapor into contact with the carbide at a flow rate of 10 liters (L) or more and 300 liters (L) or less per minute for 1 minute or more and 1,440 minutes or less can be mentioned. Note that an inert gas such as nitrogen may be used in combination with the active gas.

[0080] The activation treatment is preferably performed using a rotary kiln. By using a rotary kiln, the activated product whose mass has become lighter as the activation of the carbide progresses can remain in the kiln furnace without scattering outside the furnace. Therefore, since the carbide can be more sufficiently activated, there is a tendency to obtain an activated product in which pores effective for the adsorption of the palladium complex are sufficiently developed.

[0081] Also, by using a rotary kiln, it becomes possible to efficiently bring the carbide and the active gas into contact with each other. As a result, there is a tendency to suitably produce a carbonaceous material having high adsorption performance for various palladium complexes such as a palladium catalyst.

[0082] When performing the activation treatment using a rotary kiln, the carbide introduced into the rotary kiln preferably has a particle size that is retained on a standard sieve wire mesh specified in JIS Z8801-1:2019, more preferably 70 mesh (mesh opening size: 243 μm) or larger and smaller than 2 mesh (mesh opening size: 10.7 mm), and even more preferably 32 mesh (mesh opening size: 490 μm) or larger and smaller than 2 mesh (mesh opening size: 10.7 mm). When the particle size of the carbide is within the above range, the activated product whose mass has become lighter as the activation of the carbide progresses stays in the kiln more, making it possible to perform activation more efficiently. As the carbide, carbide whose particle size has been adjusted by cutting the raw material to a desired size in advance before the carbonization process may be used, or carbide whose particle size has been adjusted by crushing and classifying the carbide to a desired size may also be used.

[0083] The temperature of the activation treatment is not particularly limited, but is preferably 750°C or higher and 1,200°C or lower, and more preferably 800°C or higher and 1,100°C or lower. When performing the activation treatment at such a temperature, a carbonaceous material with a mesopore ratio of 6.4% or more and 50.0% or less, a reactive black pentavalent of 1.0 g / L or more and 8.0 g / L or less, and an iodine adsorption amount of 1,000 mg / g or more and 1,600 mg / g or less can be more easily produced.

[0084] The partial pressure of the active gas is, for example, 10% or more and 100% or less, and preferably 30% or more and 100% or less.

[0085] As the active gas, it is preferable to use oxygen gas and carbon dioxide gas together with water vapor gas. In that case, the partial pressure of water vapor is preferably more than 40.0% by volume and at most 60.0% by volume, more preferably 45.0% by volume or more and 55.0% by volume or less. The partial pressure of oxygen gas is preferably more than 5.0% by volume and at most 20.0% by volume, more preferably 7.0% by volume or more and 15.0% by volume or less. The partial pressure of carbon dioxide gas is preferably 1.0% by volume or more and 15.0% by volume or less, more preferably 3.0% by volume or more and 10.0% by volume or less. In addition, as other gases, an inert gas such as nitrogen may be included. In that case, the partial pressure of the inert gas is preferably 5.0% by volume or more and less than 54.0% by volume, more preferably 20.0% by volume or more and 25.0% by volume or less. When their ratios are within the above ranges, there is a tendency to more easily produce a carbonaceous material in which the ratio of mesopores is 6.4% or more and 50.0% or less, the reactive black pentavalent is 1.0 g / L or more and 8.0 g / L or less, and the iodine adsorption amount is 1,000 mg / g or more and 1,600 mg / g or less.

[0086] The activation time can be appropriately set according to conditions such as the raw material, activation temperature, and manufacturing equipment. As the activation time, for example, it is 20 minutes or more and 48 hours or less, preferably 30 minutes or more and 36 hours or less, more preferably 40 minutes or more and 24 hours or less, still more preferably 45 minutes or more and 120 minutes or less, and even more preferably 50 minutes or more and 100 minutes or less. When the activation time is within the above range, there is a tendency to more easily produce a carbonaceous material in which the ratio of mesopores is 6.4% or more and 50.0% or less, the reactive black pentavalent is 1.0 g / L or more and 8.0 g / L or less, and the iodine adsorption amount is 1,000 mg / g or more and 1,600 mg / g or less.

[0087] Examples of the activation device for performing the activation treatment include a rotary kiln as shown in FIGS. 1 and 2. FIG. 1 is a cross-sectional view I and a side view II of the rotary kiln. FIG. 2 is a schematic cross-sectional view for explaining the rotary kiln.

[0088] As shown in FIGS. 1 and 2, a rotary kiln generally includes a tubular body 1 and stirring blades A to F disposed on the inner wall surface of the tubular body 1. The active gas is usually fed from one side to the other side, that is, in the flow direction 2 of the active gas in the tubular body 1 in the case of a rotary kiln as shown in FIGS. 1 and 2.

[0089] The material of the tubular body 1 is not particularly limited as long as it is a material used for a rotary kiln, and examples thereof include stainless steel.

[0090] In FIGS. 1 and 2, the number of stirring blades is six, but it can be appropriately adjusted according to the charging amount of the carbide 5 as the raw material. The number of stirring blades is usually 1 or more and 20 or less, preferably 3 or more and 12 or less, and more preferably 5 or more and 10 or less. Further, the stirring blades are preferably installed at equal intervals around the central axis of the tubular body 1. For example, if the number of stirring blades is six, they are installed every 60° around the central axis of the tubular body 1.

[0091] The height of the stirring blade (the height in the direction from the wall of the tubular body 1 toward the center) can be appropriately set according to the size of the tubular body 1 and the charging amount of the carbide 5, but it is preferable that the stirring blade has a height such that it can be visually recognized without being covered by the carbide 5 charged into the tubular body 1. Specifically, when the stirring blade is located at the bottommost surface of the tubular body 1 (the position of the stirring blade B in the right figure of FIG. 2), the height of the stirring blade is preferably such that it is covered by the carbide 5 by 1 / 2 or more and 2 / 3 or less from the bottommost surface. The height of the stirring blade is more preferably 10% or more and 30% or less with respect to the inner radius of the tubular body 1.

[0092] The thickness of the stirring blade (the thickness in the rotational direction 3 of the tubular body 1) can be appropriately set according to the size of the tubular body 1 and the charging amount of the carbide 5, but it is preferable that the stirring blade has a thickness such that it is not damaged by the carbide 5 charged into the tubular body 1. Specifically, the thickness of the stirring blade is usually 1% or more and 100% or less, preferably 20% or more and 90% or less, and more preferably 30% or more and 95% or less with respect to the wall thickness of the tubular body 1.

[0093] The material of the stirring blades is not particularly limited as long as it is a material used for a rotary kiln. For example, stainless steel can be mentioned.

[0094] By arranging the stirring blades inside the tubular body 1 in this way, the contact efficiency between the carbide 5 and the active gas tends to be further improved. From this, it tends to be easier to manufacture a carbonaceous material having a desired specific surface area.

[0095] As shown in FIG. 2, an appropriate amount of the carbide 5 is charged inside the tubular body 1. Then, as the tubular body 1 rotates in the rotational direction 3 of the tubular body, for example, the carbide 5 collected by the stirring blade A is lifted by the stirring blade A, and then, while being mixed toward the dropping direction 4 of the carbide, it contacts the active gas and is activated while being collected between the stirring blades A and B. By rotating the tubular body 1 in this way, the carbide 5 is mixed while passing over the stirring blades A to F, and contacts and is activated with the active gas efficiently and uniformly. From this, it tends to be easier to manufacture a carbonaceous material having a desired pore size distribution.

[0096] In this way, by using a rotary kiln as the activation device, a carbonaceous material having a mesopore ratio of 6.4% or more and 50.0% or less, a reactive black pentavalent content of 1.0 g / L or more and 8.0 g / L or less, and an iodine adsorption amount of 1,000 mg / g or more and 1,600 mg / g or less can be more easily manufactured.

[0097] By the above activation step, an activated product is obtained.

[0098] The method for manufacturing a carbonaceous material may include a washing step and / or a drying step, etc., in which after the activation step, the activated product is subjected to a washing treatment and / or a drying treatment, etc. The conditions in these steps are not particularly limited, and known conditions can be adopted. Also, the following washing step and drying step may be referred to.

[0099] (Washing step) The carbonaceous material is preferably obtained through a washing step of washing the activated product obtained in the activation step. As the washing, acid washing is more preferable. By undergoing such a washing step, there is a tendency to more easily produce a carbonaceous material in which the proportion of mesopores is 6.4% or more and 50.0% or less, the reactive black pentavalent is 1.0 g / L or more and 8.0 g / L or less, and the iodine adsorption amount is 1,000 mg / g or more and 1,600 mg / g or less.

[0100] Examples of the type of acid used for acid washing include mineral acids such as hydrochloric acid and nitric acid; and organic acids such as formic acid and acetic acid. These acids may be used alone or in combination of two or more.

[0101] The acid concentration, and the temperature and time in acid washing may be appropriately adjusted so that the target carbonaceous material can be obtained.

[0102] (Drying step) The carbonaceous material is preferably obtained through a drying step of drying the washed product obtained in the washing step.

[0103] The drying method is not particularly limited, and known drying methods such as natural drying, heat drying, and hot air drying can be used. As the drying method, a method of heating and / or reducing pressure is preferable. As the method of drying by heating, a hot air drying method is preferable from the viewpoint of no drying unevenness and stable drying. In the drying conditions, it is preferable to dry until the moisture content of the carbonaceous material becomes 20.0 mass% or less, and more preferably until it becomes 10.0 mass% or less.

[0104] Examples of the heating method include heating methods by, for example, a stationary type constant temperature dryer; a stationary type hot air dryer; a vacuum dryer; a rotary evaporator; a mixed dryer such as a conical dryer and a Nauta dryer. The heating temperature may be a temperature at which the carbonaceous material hardens and does not melt, and for example, 40°C or more and 300°C or less is preferable.

[0105] As the decompression method, for example, a decompression method using an oil pump, an oil-free pump, an aspirator, etc. can be mentioned. The pressure in the decompression method is usually 0.00001 MPa or more and 0.05 MPa or less.

[0106] The drying time depends on the drying temperature, but is usually about 1 minute or more and 20 hours or less.

[0107] The carbonaceous material thus obtained may be used as it is, or, if necessary, by a known method, adjustment of the particle size by crushing, pulverizing, and classification; for example, purification by additional washing using water, an organic solvent, an aqueous acid solution, and an aqueous alkali solution; and imparting durability and structural adjustment by additional heat treatment to obtain a carbonaceous material.

[0108] [Use] The carbonaceous material can be suitably used for various applications such as removing, adsorbing, concentrating, and recovering various palladium complexes such as palladium catalysts. Such applications may be applications that appropriately combine the operations of removal, adsorption, concentration, and recovery. Examples of such applications include wastewater treatment, waste oil treatment, catalyst recovery from reaction solutions, decolorization of products, and removal, concentration, and adsorption of impurities from reaction solutions.

[0109] The carbonaceous material is suitably used for adsorbing palladium complexes in an organic solvent. The carbonaceous material is more suitably used for adsorbing a zero-valent palladium complex and / or a divalent palladium complex in an organic solvent.

[0110] Examples of the zero-valent palladium complex include bis(dibenzylideneacetone)palladium(0) and tetrakis(triphenylphosphine)palladium(0). Since it has higher adsorption performance, the zero-valent palladium complex is preferably bis(dibenzylideneacetone)palladium(0).

[0111] Examples of the divalent palladium complex include palladium(II) acetate, palladium(II) chloride, and dichlorobis(triphenylphosphine)palladium(II). Since it has higher adsorption performance, the divalent palladium complex is preferably palladium(II) acetate.

[0112] Examples of the organic solvent include methylene chloride, chloroform, carbon tetrachloride, ethylene chloride, trichloroethylene, tetrachloroethylene, o-dichlorobenzene, m-dichlorobenzene, Freon-112, Freon-113, HCFC, HFC, propyl bromide, butyl iodide, acetic acid, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl methacrylate, diethyl carbonate, ethyl formate, diethyl ether, dipropyl ether, tetrahydrofuran, dibutyl ether, anisole, methanol, ethanol, isopropanol, n-butanol, 2-butanol, isobutanol, t-butanol, allyl alcohol, pentanol, heptanol, ethylene glycol, diethylene glycol, phenol, o-cresol, m-cresol, p-cresol, xylenol, acetaldehyde, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, chloroform, acetonitrile, acrylonitrile, n-hexane, isohexane, cyclohexane, methylcyclohexane, n-heptane, n-octane, n-nonane, isononane, decane, dodecane, undecane, tetradecane, decalin, benzene, toluene, m-xylene, o-xylene, p-xylene, ethylbenzene, 1,3,5-trimethylbenzene, n-methylpyrrolidone, dimethylformamide, dimethylacetamide, and dimethyl sulfoxide. These organic solvents may be used alone or in a mixture of multiple types.

[0113] [Adsorption Method of Palladium Complex] The adsorption method of the palladium complex of the present embodiment includes an adsorption step of adsorbing the palladium complex onto a carbonaceous material. As a method of adsorbing the palladium complex, for example, a method of adsorbing the palladium complex onto a carbonaceous material to concentrate the palladium complex in the carbonaceous material can be mentioned. The concentration method may have the same steps as known adsorption methods, concentration methods, and recovery methods of metallic palladium, etc., except that the carbonaceous material of the present embodiment is used as the carbonaceous material.

[0114] In the adsorption step, for example, the palladium complex is adsorbed onto the carbonaceous material by bringing the palladium complex into contact with the carbonaceous material.

[0115] [Apparatus] The apparatus includes a carbonaceous material. The apparatus may have the same configuration as a known apparatus, except that the carbonaceous material of the present embodiment is used as the carbonaceous material.

[0116] The function of the carbonaceous material is utilized by an apparatus including the same. The apparatus is preferably a processing apparatus. In the present specification, the "processing apparatus" is not particularly limited as long as it is an apparatus that can remove, adsorb, concentrate, and recover various palladium complexes such as palladium catalysts contained in objects to be processed such as wastewater, waste liquid, and oil, using the carbonaceous material of the present embodiment. Such a processing apparatus may be an apparatus in which the operations of removal, adsorption, concentration, and recovery are appropriately combined. Examples of such a processing apparatus include an apparatus including a filter, column, tank or bath, tube, cartridge, cylinder, and sheet (hereinafter, also simply referred to as "filter, etc. containing a carbonaceous material") containing a carbonaceous material, as well as a filtration apparatus, adsorption apparatus, and concentration apparatus.

[0117] The apparatus includes, for example, an adsorption section for bringing the palladium complex into contact with the carbonaceous material. In the adsorption section, an adsorbent other than the carbonaceous material according to the present embodiment may be included as necessary. Examples of such an adsorbent include activated carbon, zeolite, silica gel, activated alumina, non-woven fabric, and porous organic compounds other than the carbonaceous material according to the present embodiment.

[0118] Examples of the filtration device include a cartridge type filtration device, a membrane treatment device, and an ultrafiltration membrane device containing a carbonaceous material.

[0119] The treatment device may be provided with other adsorption filters together with a filter containing a carbonaceous material. Examples of such other adsorption filters include metal filters made of, for example, stainless steel, aluminum, bronze, copper, titanium, and nickel; resin filters made of, for example, polypropylene, polyvinyl chloride, polyvinylidene chloride, polyethylene, polyamide, and fluororesin.

[0120] Also, the treatment device may be of a batch type or a continuous type, and the carbonaceous material can be used in either mode.

Examples

[0121] Hereinafter, examples and comparative examples will be shown to more specifically explain the present invention, but the present invention is not limited by these examples in any way.

[0122] 〔Evaluation method〕 (1) BET specific surface area - The specific surface area (m 2 / g) of the carbonaceous material determined by the BET method from the nitrogen adsorption isotherm at -196 °C was measured. 2 / g) was measured. Specifically, the BET specific surface area (m 2 / g) was determined as follows. That is, first, a specific surface area / pore size distribution measuring device (BELSORP (registered trademark)-miniII (product name) manufactured by Microtrac BEL Co., Ltd.) was used, and the carbonaceous material was heated at 250 °C for 3 hours under reduced pressure (vacuum degree: 0.1 kPa or less), and then the nitrogen adsorption isotherm of the carbonaceous material at -196 °C was measured. Using the obtained nitrogen adsorption isotherm, by BET analysis, a straight line in the region of relative pressure P / P0 = 0.01 or more and 0.10 or less was obtained from the obtained curve by the multi-point method, and the BET specific surface area was calculated from this straight line.

[0123] (2) Pore volume of mesopores - N at -196 °C 2 The pore volume (cm 3 / g) of the mesopores of the carbonaceous material determined by the BJH method from the adsorption isotherm was measured. Specifically, using the nitrogen adsorption isotherm used in the calculation of the above BET specific surface area, a curve was obtained by BJH analysis in the region where the relative pressure P / P0 is 0.385 or more and 0.99 or less. From the obtained curve, the cumulative pore volume for each pore diameter was calculated, and by subtracting the cumulative pore volume with a pore diameter up to 2.0 nm from the cumulative pore volume with a pore diameter up to 50.0 nm, the pore volume of the mesopores with a pore diameter of 2.0 nm or more and 50.0 nm or less was calculated.

[0124] (3) BJH specific surface area - N at -196 °C 2 The specific surface area (m 2 / g) of the carbonaceous material determined by the BJH method from the adsorption isotherm was measured. The BJH specific surface area is the specific surface area determined from the pore volume and pore diameter of the carbonaceous material measured based on the BJH method. Specifically, using the nitrogen adsorption isotherm used in the calculation of the above BET specific surface area, a curve was obtained by BJH analysis in the region where the relative pressure P / P0 is 0.385 or more and 0.99 or less. From the obtained curve, the pore volume of the mesopores was calculated for each pore diameter in the range of 2.0 nm or more and 50.0 nm or less, and using those values and the following formula (I), the specific surface area was calculated. By adding up the specific surface areas for each obtained pore diameter, the BJH specific surface area of the carbonaceous material was calculated. Ap = 2 × Vp / (rp × 10 7 ) × 0.0001 ··· (I) In formula (I), Ap represents the specific surface area (m 2 / g) at a certain pore diameter, Vp represents the pore volume (cm 3 / g) at a certain pore diameter, and rp represents the pore diameter (nm).

[0125] (4) Ratio of mesopores Using the carbonaceous material, the ratio (%) of mesopores was calculated. Specifically, the ratio (%) of mesopores in the carbonaceous material was calculated from the following formula (II) using the BET specific surface area (m 2 / g) and the BJH specific surface area (m 2 / g) determined above. Ratio of mesopores = BJH specific surface area / BET specific surface area × 100 ··· (II)

[0126] (5) Reactive Black 5 Using the carbonaceous material, the content of Reactive Black 5 (g / L) was measured. Specifically, first, the carbonaceous material was pulverized so that the volume-based cumulative distribution 50% particle diameter (D50) was about 10.0 μm or less, and dried in a constant-temperature dryer at 115 °C (Yamato Scientific Co., Ltd. DVS402 (trade name)) for 3 hours. Then, it was allowed to cool to room temperature in a desiccator using silica gel as a desiccant, and the carbonaceous material after cooling was obtained.

[0127] On the other hand, a test solution A containing a phosphate buffer and Reactive Black 5 (manufactured by Sigma-Aldrich) was prepared as follows. That is, first, 7.26 g of potassium dihydrogen phosphate (manufactured by Fujifilm Wako Pure Chemical Corporation) and 28.66 g of disodium hydrogen phosphate dodecahydrate (manufactured by Fujifilm Wako Pure Chemical Corporation) were dissolved in 2 L of distilled water to prepare a phosphate buffer (pH: 7.0). Then, for 1 L of the obtained phosphate buffer, Reactive Black 5 was added in the range of about 0.5 g or more and 1.2 g or less to prepare test solution A. At that time, the amount of Reactive Black 5 was adjusted as follows. That is, the amount of Reactive Black 5 added to 1 L of the phosphate buffer was appropriately adjusted so that the absorbance of the solution obtained by diluting the obtained test solution A 20-fold with distilled water was in the range of 1.18 or more and 1.23 or less. The absorbance was the absorbance at a wavelength of 594 nm, and was measured using a quartz cell with an optical path length of 10 mm and a double-beam spectrophotometer (Hitachi High-Tech Corporation U-2910 (trade name)). The solution obtained by diluting the test solution A obtained as described above 20-fold was used as test solution B, and this test solution B was used for the following absorbance measurement.

[0128] Next, an arbitrary mass of the above-mentioned carbonaceous material after cooling is taken into a 100 mL Erlenmeyer flask with a stopper (an amount such that the residual rate of reactive black 5 contained in the filtrate is about 10% according to the following formula (IV)). The carbonaceous material is added to 50 mL of the test solution A prepared above, and using a shaking thermostat (Water Bath Shaker MM-10 (trade name) manufactured by Taitec Co., Ltd.), it is shaken in a water bath at 40 °C at a speed of 150 times / min for 5 hours to obtain a mixed solution. Then, the mixed solution is filtered using a membrane filter (DISMIC (registered trademark) 25HP045AN (trade name) manufactured by Advantec Toyo Co., Ltd.) to obtain a filtrate.

[0129] Using a glass cell with an optical path length of 10 mm, the absorbance at a wavelength of 594 nm of the obtained test solution B and the filtrate was measured with an ultraviolet-visible spectrophotometer (Double Beam Spectrophotometer U-2910 (trade name) manufactured by Hitachi High-Tech Corporation). Using these absorbances, the adsorption amount of reactive black 5 per 1 g of carbonaceous material (hereinafter referred to as "RB5 adsorption amount per 1 g of carbonaceous material ( / g)") was calculated according to the following formula (III). RB5 adsorption amount per 1 g of carbonaceous material ( / g) = (Absorbance of test solution B at wavelength 594 nm × 20 - Absorbance of filtrate at wavelength 594 nm) / Mass of carbonaceous material (g) ··· (III)

[0130] Also, the residual rate of reactive black 5 contained in the filtrate (hereinafter simply referred to as "RB5 residual rate (%)") was calculated according to the following formula (IV). RB5 residual rate (%) = (Absorbance of filtrate at wavelength 594 nm / Absorbance of test solution B at wavelength 594 nm × 20) × 100 ··· (IV)

[0131] Next, a power approximation curve was created using the RB5 residual rate (%) on the horizontal axis and the RB5 adsorption amount per 1 g of the carbonaceous material ( / g) on the vertical axis. Using the power approximation formula, the adsorption amount of reactive black 5 at a reactive black 5 residual rate of 1% (hereinafter simply referred to as "RB5 adsorption amount ( / g) at an RB5 residual rate of 1%") was determined, and the reactive black 5 valence (g / L) was calculated according to formula (V). Reactive black 5 valence (g / L) = (Absorbance at a wavelength of 594 nm of test solution B × 20 × 0.99 / RB5 adsorption amount ( / g) at an RB5 residual rate of 1%) / 0.05 (L) ··· (V) Note that 0.05 (L) in formula (V) is the amount of the test solution.

[0132] (6) Iodine adsorption amount (iodine adsorption performance) The iodine adsorption amount (mg / g) of the carbonaceous material was measured and calculated. Specifically, the measurement of the iodine adsorption amount was carried out in accordance with JIS K 1474 (2014). That is, first, the carbonaceous material was pulverized until it passed through a 45 μm sieve by 90% or more in accordance with JIS Z 8801-1, and dried in a constant temperature dryer (DVS402 (trade name) manufactured by Yamato Scientific Co., Ltd.) at 115°C for 3 hours. Then, it was allowed to cool to room temperature in a desiccator using silica gel as a desiccant, and the carbonaceous material after cooling was obtained.

[0133] On the other hand, 25.0 g of potassium iodide (manufactured by Fujifilm Wako Pure Chemical Corporation) and 13.0 g of iodine (manufactured by Fujifilm Wako Pure Chemical Corporation) were dissolved in approximately 1 L of distilled water to prepare an iodine solution. The iodine solution was titrated with a 0.1 mol / L sodium thiosulfate solution (manufactured by Fujifilm Wako Pure Chemical Corporation), and an appropriate amount of distilled water was added to the iodine solution to prepare a 0.05 mol / L iodine solution.

[0134] Next, weigh an arbitrary amount of the carbonaceous material after the above-mentioned cooling (an amount such that the iodine residual concentration in the supernatant of the following filtrate is approximately 2.5 g / L), place it in a 100 mL Erlenmeyer flask with a stopper, and further add 50 mL of the above 0.05 mol / L iodine solution in its entirety using a pipette. At room temperature (20°C or higher and 30°C or lower), use a shaker (medium-sized shaker reciprocating shaker NR-10 (trade name) manufactured by Taitec Co., Ltd.) to shake at 200 times / min for 15 minutes to adsorb iodine onto the carbonaceous material and obtain a mixed solution. Then, filter the mixed solution using a cellulose mixed ester membrane filter (A045A025A (trade name) manufactured by Advantec Toyo Co., Ltd.) to obtain a filtrate. Pipette 10 mL of the supernatant of the filtrate in its entirety, titrate it with a 0.1 mol / L sodium thiosulfate solution (manufactured by Fujifilm Wako Pure Chemical Corporation, factor: 1.000), and calculate the iodine residual concentration according to the following formula (VI). Iodine residual concentration (g / L) = Amount (mL) of 0.1 mol / L sodium thiosulfate solution used for titration × Factor of 0.1 mol / L sodium thiosulfate solution × 12.69 / 10 ··· (VI)

[0135] Calculate the iodine adsorption amount per 1 g of the carbonaceous material according to the following formula (VII). Iodine adsorption amount per 1 g of carbonaceous material = (10 × Factor of 0.05 mol / L iodine solution - Amount (mL) of 0.1 mol / L sodium thiosulfate solution used for titration × Factor of 0.1 mol / L sodium thiosulfate solution) × 12.69 × 5 / Mass (g) of carbonaceous material ··· (VII)

[0136] Note that the factor of the 0.05 mol / L iodine solution was calculated according to formula (VIII). Factor of 0.05 mol / L iodine solution = (Amount (mL) of 0.1 mol / L sodium thiosulfate solution used for titration × Factor of 0.1 mol / L sodium thiosulfate solution) / 10 ··· (VIII)

[0137] From the Freundlich adsorption isotherm, an adsorption isotherm was created with the horizontal axis representing the residual iodine concentration and the vertical axis representing the iodine adsorption amount per gram of the carbonaceous material. The iodine adsorption amount per gram of the carbonaceous material (mg / g) at a residual iodine concentration of 2.5 g / L was calculated. This iodine adsorption amount was taken as the iodine adsorption performance.

[0138] (7) pH The pH of the aqueous suspension was measured using the carbonaceous material. Specifically, first, in accordance with JIS K 1474 (2014), the carbonaceous material with a particle size of less than 150 μm was made into powder, and the carbonaceous material with a particle size of 150 μm or more was made into granules. Then, for the powdered carbonaceous material, 1.0 g was weighed in terms of dry mass, and for the granular carbonaceous material, 3.0 g was weighed in terms of dry mass. After that, the weighed carbonaceous material was added to a 100 mL tall beaker, and 100 mL of distilled water was further added to obtain a mixed solution. Using a hot plate (Ceramic Hot Plate CHP - 400DN (trade name) manufactured by AS ONE Corporation), the obtained mixed solution was gently boiled for 5 minutes. Then, the mixed solution was allowed to cool to room temperature, distilled water was added so that the volume of the mixed solution became 100 mL, and the suspension was obtained by stirring. The pH of the obtained suspension was measured using a pH meter (Tabletop pH Meter F - 51 (trade name) manufactured by Horiba, Ltd.). (8) Bulk density The bulk density (g / mL) measured by the tapping method was calculated using the carbonaceous material. Specifically, first, the carbonaceous material was crushed so that the 50% particle size (D50) of the volume - based cumulative distribution was about 9.0 μm or more and 11.0 μm or less, and dried in a constant - temperature dryer at 115 °C (DVS402 (trade name) manufactured by Yamato Scientific Co., Ltd.) for 3 hours. Then, it was allowed to cool to room temperature in a desiccator using silica gel as a desiccant, and the carbonaceous material after cooling was obtained.

[0139] Weighed 5.0 g of the carbonaceous material after the above-mentioned cooling, roughly divided it into three equal parts, and put a part (about 1 / 3 of the amount) of the carbonaceous material into a 150 mL graduated cylinder (inner diameter: 31 mm, manufactured by Tsutsui Rikagaku Kikai Co., Ltd.). A rubber stopper was placed on the graduated cylinder and set on an automatic tapping device (powder reduction degree measuring machine TPM-3A type (trade name) manufactured by Tsutsui Rikagaku Kikai Co., Ltd.), and tapping was performed for 1 minute at a vibration amplitude of 45 mm and a vibration frequency of 35 - 36 times / min. After the tapping was completed, another part (about 1 / 3 of the amount) of the carbonaceous material among the previously divided three equal parts was further added to the graduated cylinder, a rubber stopper was placed on it, and tapping was performed for 1 minute under the same conditions as above. Then, the last part (about 1 / 3 of the amount) of the carbonaceous material among the previously divided three equal parts was further added to the graduated cylinder, a rubber stopper was placed on it, and tapping was performed for 30 minutes under the same conditions as above.

[0140] After the tapping was completed, the rubber stopper was removed, the upper surface of the sample in the graduated cylinder was flattened with a spatula, etc., and the sample volume (mL) was visually measured from the scale of the graduated cylinder. Using the measured sample volume, the packing density measured by the tapping method was calculated according to the following formula (IX). Packing density (g / mL) = mass of carbonaceous material (g) / measured sample volume (mL) ··· (IX)

[0141] (9) Removal rate of palladium (II) complex Using the carbonaceous material, the adsorption performance for divalent palladium (palladium (II)) complex was measured. Specifically, first, palladium (II) acetate (manufactured by Fujifilm Wako Pure Chemical Corporation) was dissolved in toluene to prepare a palladium solution with a palladium concentration of 50 ppm (hereinafter, also simply referred to as "palladium (II) solution for adsorption performance measurement"). 25 mL of the palladium solution was put into a 100 mL conical flask with a stopper, and 0.5 g of the carbonaceous material was further added. Then, at 25 °C, using a shaking thermostatic bath (Cool Bath Shaker ML-10F (trade name) manufactured by Taitec Corporation), it was shaken for 1 hour to obtain a mixed solution. Then, the mixed solution was filtered using a membrane filter (DISMIC (registered trademark) 25HP (trade name) manufactured by Advantec Toyo Co., Ltd.) to obtain a filtrate.

[0142] Using a glass cell with an optical path length of 1 mm, the absorbances at a wavelength of 393 nm were measured for the palladium(II) solution for adsorption performance measurement and the filtrate obtained above, respectively, using an ultraviolet-visible spectrophotometer (double-beam spectrophotometer U-2910 (trade name) manufactured by Hitachi High-Tech Corporation). Using these absorbances and a calibration curve prepared in advance, the residual concentrations (ppm) of the respective palladium(II) complexes in the palladium(II) solution for adsorption performance measurement and the filtrate obtained above were calculated. The calibration curve was prepared as follows. That is, solutions in which a palladium solution with a palladium(II) complex concentration of 50 ppm was diluted 5-fold, 50-fold, and 100-fold with toluene were prepared respectively. Then, using these solutions, the absorbances at a wavelength of 393 nm were measured in the same manner as the above measurement method, and a calibration curve was prepared based on the measurement results.

[0143] Next, using the obtained residual concentration (ppm) of the palladium(II) complex, the removal rate (%) of the palladium(II) complex was calculated by the following formula (X). The removal rate of the palladium(II) complex was regarded as the adsorption performance of the carbonaceous material for the palladium(II) complex. Removal rate of palladium(II) complex (%) = Residual concentration of palladium(II) complex in filtrate (ppm) / Residual concentration of palladium(II) complex in palladium(II) solution for adsorption performance measurement (ppm) × 100) ··· (X)

[0144] (10) Removal rate of palladium(0) complex Using the carbonaceous material, the adsorption performance for the palladium(0) complex in the zero-valent state was measured. Specifically, first, bis(dibenzylideneacetone)palladium(0) (manufactured by Fujifilm Wako Pure Chemical Corporation) was dissolved in toluene to prepare a palladium solution with a palladium concentration of 50 ppm (hereinafter, also simply referred to as "palladium(0) solution for adsorption performance measurement"). 25 mL of the palladium solution was placed in a 100 mL Erlenmeyer flask with a stopper, and 0.5 g of the carbonaceous material was further added. Then, at 25°C, using a shaking thermostatic bath (Cool Bath Shaker ML-10F (trade name) manufactured by Taitec Corporation), it was shaken for 1 hour to obtain a mixed solution. Thereafter, the mixed solution was filtered using a membrane filter (DISMIC (registered trademark) 25HP (trade name) manufactured by Advantec Toyo Co., Ltd.) to obtain a filtrate.

[0145] Using a glass cell with an optical path length of 1 mm and a double-beam spectrophotometer U-2910 (trade name) manufactured by Hitachi High-Tech Corporation, the absorbances of the palladium(0) solution for adsorption performance measurement and the filtrate obtained above were measured at a wavelength of 523 nm, respectively. Using those absorbances and a calibration curve prepared in advance, the residual concentrations (ppm) of the respective palladium(0) complexes in the palladium(0) solution for adsorption performance measurement and the filtrate obtained above were calculated. The calibration curve was prepared as follows. That is, palladium solutions with a palladium(0) complex concentration of 50 ppm were each diluted 5-fold, 50-fold, and 100-fold with toluene. Thereafter, using those solutions, the absorbance at a wavelength of 523 nm was measured in the same manner as the above measurement method, and a calibration curve was prepared based on those measurement results.

[0146] Next, using the obtained residual concentration (ppm) of the palladium(0) complex, the removal rate (%) of the palladium(0) complex was calculated by the following formula (XI). The removal rate of the palladium(0) complex was regarded as the adsorption performance of the carbonaceous material for the palladium(0) complex. Removal rate of palladium(0) complex (%) = Residual concentration of palladium(0) complex in filtrate (ppm) / Residual concentration of palladium(0) complex in palladium(0) solution for adsorption performance measurement (ppm) × 100) ··· (XI)

[0147] 〔Example 1〕 (Carbonization process) Carbides were obtained by carbonizing wood powder produced in Japan and Malaysia at a temperature of 550 °C for about 8 hours.

[0148] (Activation process) The obtained carbides were put into a rotary kiln equipped with stirring blades in a furnace heated to 850 °C as shown in FIGS. 1 and 2, at about 0.06 times the volume of the rotary kiln of 1 m 3 Then, while rotating the kiln at a rotational speed of 3.0 rpm, a gas (50.0 vol% water vapor, 10.0 vol% oxygen, 35.0 vol% nitrogen, and 5.0 vol% carbon dioxide) was introduced into the kiln, and an activation treatment was performed for 60 minutes to obtain an activated product.

[0149] In the rotary kiln used, six stirring blades were installed at 60° intervals around the central axis of the pipe body. Also, the height of the stirring blades was 15% or more and 25% or less of the inner radius of the pipe body, and the thickness of the stirring blades was 40% or more and 80% or less of the thickness of the pipe body.

[0150] (Pickling process and drying process, etc.) The obtained activated product was washed with dilute hydrochloric acid, and then thoroughly washed and dried with water to remove the remaining hydrochloric acid, obtaining a dried product. Then, the obtained dried product was pulverized to obtain a pulverized carbonaceous material 1 which is activated carbon.

[0151] 〔Example 2〕 In the activation process, a pulverized carbonaceous material 2 which is activated carbon was obtained in the same manner as in Example 1, except that the activation treatment was performed for 80 minutes.

[0152] 〔Example 3〕 An activated product was obtained in the same manner as in Example 1. Then, for the obtained activated product, drying and pulverization were performed in the same manner as in Example 1, except that washing was not carried out, to obtain a pulverized carbonaceous material 3 which is activated carbon.

[0153] 〔Example 4〕 In the activation process, except that the activation treatment was carried out for 90 minutes, a pulverized carbonaceous material 4, which is activated carbon, was obtained in the same manner as in Example 1.

[0154] [Comparative Example 1] (Carbonization process) Carbides were obtained by carbonizing coconut shells produced in the Philippines at a temperature of 550 °C for about 8 hours.

[0155] (Activation process) The obtained carbide was introduced into a rotary kiln equipped with stirring blades in a furnace heated to 900 °C as shown in FIGS. 1 and 2, at about 0.06 times the volume of the rotary kiln of 1 m 3 . Then, while rotating the kiln at a rotational speed of 3.0 rpm, a gas (40.0 vol% water vapor, 5.0 vol% oxygen, 50.0 vol% nitrogen, and 5.0 vol% carbon dioxide) was introduced into the kiln, and an activated product was obtained by performing an activation treatment for 250 minutes.

[0156] In the rotary kiln used, six stirring blades were installed at 60° intervals around the central axis of the pipe body. Also, the height of the stirring blade was 15% or more and 25% or less with respect to the inner radius of the pipe body, and the thickness of the stirring blade was 40% or more and 80% or less with respect to the thickness of the pipe body.

[0157] (Pickling and drying processes, etc.) For the obtained activated product, pickling, drying, and pulverization were carried out in the same manner as in Example 1 to obtain a pulverized carbonaceous material 5, which is activated carbon.

[0158] [Comparative Example 2] In the activation process, except that the activation treatment was carried out for 130 minutes, a pulverized carbonaceous material 6, which is activated carbon, was obtained in the same manner as in Comparative Example 1.

[0159] [Comparative Example 3] An activated product was obtained in the same manner as in Comparative Example 2. Then, for the obtained activated product, drying and pulverization were carried out in the same manner as in Example 1 except that washing was not performed to obtain a pulverized carbonaceous material 7, which is activated carbon.

[0160] [Comparative Example 4] An activated product was obtained in the same manner as in Comparative Example 2. Then, the obtained activated product was washed with dilute hydrochloric acid and then with dilute nitric acid. Next, it was thoroughly washed with water and dried to remove the remaining nitric acid, obtaining a dried product. Then, the obtained dried product was pulverized to obtain a pulverized carbonaceous material 8 which is activated carbon.

[0161] [Table 1] [Industrial Applicability]

[0162] The carbonaceous material of this embodiment can be suitably used for various applications such as removing, adsorbing, concentrating, and recovering various palladium complexes such as palladium catalysts. [Explanation of Signs]

[0163] A, B, C, D, E, F... stirring blades, 1... tube body, 2... flow direction of the active gas, 3... rotation direction of the tube body, 4... falling direction of the carbide, 5... carbide.

Claims

1. A carbonaceous material having a mesopore ratio of 6.4% or more and 50.0% or less, a reactive black pentavalent of 1.0 g / L or more and 8.0 g / L or less, and an iodine adsorption amount of 1,000 mg / g or more and 1,600 mg / g or less.

2. - The pore volume of mesopores determined by the BJH method from the adsorption isotherm of N at -196 °C is 0.16 cm ２ / g or more and 0.60 cm ３ / g or less. The carbonaceous material according to claim 1. ３ ​

3. - The specific surface area determined by the BET method from the adsorption isotherm of N at -196°C is ２ 950 m ２ / g or more and 1,700 m ２ / g or less, the carbonaceous material according to claim 1.

4. - The specific surface area determined by the BJH method from the adsorption isotherm of N at -196 °C is 23 m ２ / g or more and 500 m ２ / g or less. The carbonaceous material according to claim 1. ２ ​

5. The carbonaceous material according to claim 1, wherein the pH is 4.5 or more and 9.5 or less.

6. The carbonaceous material according to claim 1, wherein the bulk density measured by the tapping method is 0.20 g / mL or more and 0.55 g / mL or less.

7. The carbonaceous material according to any one of claims 1 to 6, which is used for the adsorption of zero-valent palladium complex and / or divalent palladium complex in an organic solvent.

8. A carbonization step of carbonizing a raw material to obtain a carbide, An activation step of activating the carbide to obtain an activated product, and a method for producing the carbonaceous material according to any one of claims 1 to 6.

9. The production method according to claim 8, further comprising a washing step of washing the activated product.

10. The production method according to claim 8, wherein the raw material is at least one selected from the group consisting of coconut shells and wood powder.

11. A method for adsorbing a palladium complex, comprising an adsorption step of adsorbing a palladium complex onto the carbonaceous material according to any one of claims 1 to 6.

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