A filtration aid, an adsorption column using the filtration aid, a filtration method using a filter material containing the filtration aid, a method for manufacturing an adsorption column using the filtration aid, and a method for separating and recovering metals and / or metal ions using the adsorption column.

Abstract

The problem that this invention aims to solve is to provide a filter aid that, when used in an adsorption column, has liquid permeability at or above the level of the conventional technology. Furthermore, it aims to provide a filter aid that allows for easy recycling of the adsorbent packing and the filter aid when porous PAS resin is used as the adsorbent. In addition, it aims to provide an adsorption column using the filter aid, a filtration method using a filter material containing the filter aid, a method for manufacturing an adsorption column using the filter aid, and a method for separating and recovering metals and / or metal ions using the adsorption column. [Solution] The filtration aid of the present invention has a cumulative 90% particle size (D90) of 1 mm or less in volume-based particle size distribution, and a cumulative 50% particle size (D50) of 5 μm or more and 600 μm or less, and a bulk density of 300 kg / m³. 3 More than 700kg / m 3 It consists of the following polyarylene sulfide resin particles.

Description

[Technical Field]

[0001] The present invention relates to a filtration aid, an adsorption column using the filtration aid, a filtration method using a filter material containing the filtration aid, a method for manufacturing an adsorption column using the filtration aid, and a method for separating and recovering metals and / or metal ions using the adsorption column. [Background technology]

[0002] In recent years, from the perspective of the effective use of valuable resources for sustainable development and the prevention of environmental pollution, efficient recovery technologies for metal atoms from solutions containing metal atoms, which are valuable resources, have attracted attention. In particular, precious metals such as platinum group metals, gold, and silver are highly valuable, and because their producing countries are concentrated in certain areas, competition to recover precious metals from waste liquids such as industrial catalysts and metal plating solutions is intensifying.

[0003] Solvent extraction is a method used to recover precious metals from wastewater, but the process is complicated, and the large size of the equipment and the treatment of the large quantities of wastewater that do not contain precious metals are problematic. Other methods, such as contacting the wastewater with adsorbents like activated carbon or ion exchange resins, are also already in practical use. However, activated carbon has low selectivity for precious metals. Ion exchange resins have high selectivity due to the functional groups of their side chains, but most of them have limitations such as being limited to aqueous systems or having large swelling and shrinking properties in solvents.

[0004] On the other hand, in recent years, there have been proposals to use porous materials made of polyarylene sulfide (hereinafter sometimes referred to as PAS) resin as adsorbents, taking advantage of its excellent heat resistance and chemical resistance. As a method for producing porous materials made of PAS resin, for example, Patent Document 1 discloses a method for producing a PPS porous material in which the thermoplastic resin is removed from a resin molded article having a co-continuous structure obtained by heat-treating polyphenylene sulfide (hereinafter sometimes referred to as PPS) and a thermoplastic resin.

[0005] However, the inventors discovered that when the obtained PAS porous material is packed into a column vessel to form an adsorption column, the PAS porous material forms a compressible cake. Although high pressure is required to ensure liquid permeability, column vessels made of resin, which are generally acid-resistant, have low pressure resistance, so the amount of liquid that can pass through is greatly limited in adsorption columns using PAS porous material. In addition, diatomaceous earth (hereinafter sometimes referred to as radiolite) is generally used as a filter aid to improve the liquid permeability of adsorption columns, but once diatomaceous earth and PAS porous material are mixed, it is difficult to separate the two, so the PAS porous material packed into the column vessel may become non-recyclable industrial waste. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2015-000946 [Overview of the project] [Problems that the invention aims to solve]

[0007] The problem that the present invention aims to solve is to provide a filtration aid that, when used in an adsorption column, has liquid permeability at or above the level of the conventional technology. A further problem that the present invention aims to solve is to provide a filtration aid that allows for easy recycling of the adsorbent and filtration aid, which are the packing materials, when porous PAS resin is used as the adsorbent. Furthermore, the present invention aims to solve is to provide an adsorption column using the filtration aid, a filtration method using a filter material containing the filtration aid, a method for manufacturing an adsorption column using the filtration aid, and a method for separating and recovering metals and / or metal ions using the adsorption column. [Means for solving the problem]

[0008] As a result of repeated studies to solve the above problems, the inventors have found that by using a PAS resin as a filter aid for an adsorption column and appropriately controlling the particle size distribution and bulk density of the particles of the PAS resin as the filter aid, the above problems can be solved, and the present invention has been completed.

[0009] That is, the present invention includes the following aspects. [1] A filter aid comprising PAS resin particles having a cumulative 90% particle diameter (D90) of 1 mm or less and a cumulative 50% particle diameter (D50) of 5 μm or more and 600 μm or less on a volume basis, and having a bulk density of 300 kg / m 3 or more and 700 kg / m 3 or less. [2] The filter aid according to [1], having a cumulative 90% particle diameter (D90) of 10 μm or more and 1 mm or less on a volume basis. [3] An adsorption column comprising a column container and a packing filled in the column container, wherein the packing comprises (i) a porous PAS resin having a specific surface area of 1 m 2 / g or more and 300 m 2 / g or less, a cumulative 50% particle diameter (D50) of 10 μm or more on a volume basis, and a bulk density of 700 kg / m 3 or less, and (ii) the filter aid according to [1] or [2], and the mixing ratio of the filter aid and the porous PAS resin in the packing is 1:99 or more and 50:50 or less (parts by mass), and the packing ratio of the packing is 0.05 or more and 0.3 or less. [4] A raw material resin preparation step of preparing a raw material PAS resin having a cumulative 90% particle diameter (D90) of 300 μm or less on a volume basis, a compression step of compressing the raw material PAS resin obtained in the raw material resin preparation step at 25°C or more and 80°C or less to obtain a compressed PAS resin, A crushing step is performed to obtain crushed PAS resin by crushing the compressed PAS resin obtained in the compression step using a crusher, A sieving step is performed to classify the pulverized PAS resin obtained in the pulverization step and recover pulverized PAS resin particles in which the cumulative 90% particle size (D90) of the volume-based particle size distribution is 1 mm or less. A method for producing a filtration aid containing [a specific substance]. [5] Compressed PAS resin is obtained by compressing the raw material PAS resin using a roll-type compression granulator. A method for producing the filtration aid described in [4]. [6] The compressed PAS resin is crushed using a roll-type compression granulator to obtain crushed PAS resin. A method for producing a filtration aid as described in [4] or [5]. [7] The pulverized PAS resin is screened using a vibrating sieve to recover pulverized PAS resin particles in which the cumulative 90% particle size (D90) of the volume-based particle size distribution is 1 mm or less. A method for producing a filtration aid as described in any of [4] to [6]. A packing step in which a packing material containing a filter aid manufactured by the methods of [8] [4]~[7] and porous PAS resin is packed into a column vessel, The packing step includes compressing the packing material packed into the column container in the packing step, In the filling step, the filter aid and the porous PAS resin in the filler are filled in a ratio of 1:99 or more and 50:50 or less (parts by mass). In the aforementioned packing compression step, the bulk density of the packing material is 400 kg / m³. 3 More than 600kg / m 3 A method for manufacturing an adsorption column, which involves compressing it until it reaches the following limit. [9] The method for manufacturing an adsorption column according to [8], wherein the packing compression step is a step of compressing the packing in the column container by passing water through it. A method for separating and recovering metals and / or metal ions in a solution, comprising separating and recovering metals and / or metal ions in an adsorption column obtained by the manufacturing method described in

[10] [8] or [9]. A filtration method using a filter material containing a filter aid obtained by the manufacturing method described in

[11] [4]~[8]. [Effects of the Invention]

[0010] The present invention provides a filter aid that, when used in an adsorption column, has liquid permeability comparable to or better than that of the prior art. Furthermore, the present invention provides a filter aid that allows for easy recycling of the adsorbent and filter aid when a porous PAS resin is used as the adsorbent. In addition, the present invention provides an adsorption column using the filter aid, a filtration method using a filter material containing the filter aid, a method for manufacturing an adsorption column using the filter aid, and a method for separating and recovering metals and / or metal ions using the adsorption column. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows an adsorption column according to the present invention. [Modes for carrying out the invention]

[0012] The embodiments of the present invention (hereinafter referred to as "these embodiments") will be described in detail below. The present invention is not limited to the following description and can be implemented in various modifications within the scope of its gist.

[0013] [Definition] Prior to describing embodiments of the present invention, the definitions of bulk density, filling rate, particle size distribution, and PAS resin used herein will be explained.

[0014] -Bulk density- In this specification, bulk density is calculated by filling a container of a specified capacity with the filling material to the point of overflow using a spatula, leveling off the excess material, and then measuring the weight to the nearest 0.01 g. In this example, a 100 mL stainless steel cylindrical container with a closed bottom (50.46 mm inner diameter x 50 mm depth) is used, and the number average of three weight measurements is divided by the internal volume of the cylindrical container to calculate the bulk density (kg / m³).3 ) was calculated as

[0015] - Packing ratio - In this specification, the packing ratio is calculated using the value obtained by putting the filling material into a container of a specified volume using a scoop until it overflows, and after triturating the filling material, measuring the weight to the 0.01 g digit. In this example, the bulk density obtained by multiplying the number average value of three measurements of the weight using a 3.9 L (inner diameter 100 mm × height 500 mm) cylindrical column made of vinyl chloride by the non-volatile content was divided by the bulk volume, and further divided by the value obtained by multiplying the true density of the filling material, and was calculated as the packing ratio.

[0016] - Particle size distribution - In this specification, the particle size distribution was measured according to a conventional method using a laser diffraction / scattering type particle size distribution measuring machine (Microtrac MT3300EXII), and is the average particle diameter (D90) at 90% of the cumulative particle size distribution curve, the average particle diameter (D50) at 50%, and the average particle diameter (D10) at 10% of the cumulative particle size distribution curve.

[0017] - PAS resin - In this specification, the PAS resin has a resin structure having a structure in which an aromatic ring and a sulfur atom are bonded as a repeating unit, and in this specification, both the porous PAS resin as an adsorbent and the PAS resin as a filter aid are resins having this structure. Specifically, it is a resin having a structural part represented by the following general formula (1) and, if necessary, a trifunctional structural part represented by the following general formula (2) as repeating units.

[0018]

Chemical formula

[0019]

Chemical formula

[0020] Here, the structural part represented by the general formula (1) above is, in particular, R in the formula 1 and R 2 From the viewpoint of the mechanical strength of the PAS resin, it is preferable that the atom is a hydrogen atom, and in that case, examples include those bonded at the para position represented by the following formula (3) and those bonded at the meta position represented by the following formula (4).

[0021] [ka] Among these, the bond of the sulfur atom to the aromatic ring in the repeating unit is particularly preferable in terms of the heat resistance and crystallinity of the PAS resin if it is bonded at the para position as represented by the general formula (3) above.

[0022] Furthermore, the PAS resin may contain not only the structural parts represented by the above general formulas (1) and (2), but also structural parts represented by the following structural formulas (5) to (8) in an amount of 30 mol% or less of the total of the structural parts represented by the above general formulas (1) and (2).

[0023] [ka] In particular, in one embodiment, it is preferable that the structural parts represented by the above general formulas (5) to (8) be 10 mol% or less, from the viewpoint of heat resistance and mechanical strength of the PAS resin. When the above PAS resin contains structural parts represented by the above general formulas (5) to (8), the bonding mode may be either a random copolymer or a block copolymer.

[0024] Furthermore, the above-mentioned PAS resin may have naphthyl sulfide bonds or the like in its molecular structure, but it is preferable that the amount of naphthyl sulfide bonds is 3 mol% or less, and particularly preferable that it is 1 mol% or less, relative to the total number of moles of other structural parts.

[0025] (Filtration aid) The filtration aid according to the present invention consists of PAS resin particles having a predetermined particle size distribution and bulk density, which will be described in detail below.

[0026] First, the filter aid made of PAS resin according to the present invention preferably has a cumulative 90% particle size (D90) of 1 mm or less in its volume-based particle size distribution, a cumulative 50% particle size (D50) of 5 μm or more and 600 μm or less, and a cumulative 90% particle size (D90) of 10 μm or more and 1 mm or less. When used together with an adsorbent as packing material for an adsorption column, if the volume-based particle size distribution of the filter aid falls outside this range, it will form a dense layer of coarse and fine particles, making it impossible to ensure proper water permeability for the adsorption column. The cumulative 90% particle size (D90) of the volume-based particle size distribution of the filter aid is preferably 950 μm or less, and more preferably 900 μm or less. Furthermore, the cumulative 50% particle size (D50) of the volume-based particle size distribution of the filter aid is preferably 10 μm or more, more preferably 20 μm or more, and also preferably 550 μm or less, and more preferably 500 μm or less. By having an appropriate particle size distribution, the filter aid can form adequate voids between the adsorbents when packed into the adsorption column vessel together with the adsorbent, ensuring excellent liquid permeability and reducing filtration resistance.

[0027] Furthermore, from a similar viewpoint, it is preferable that the filter aid made of PAS resin according to the present invention has a cumulative 100% particle diameter (D100) of the volume-based particle size distribution, i.e., a maximum particle diameter of 1 mm or less.

[0028] Furthermore, the bulk density of the filter aid made of PAS resin according to the present invention is 300 kg / m³. 3 More than 700kg / m 3 The following applies: Bulk density is 300 kg / m³ 3 If the amount is less than 700 kg / m³, it will not be possible to fill the adsorption column with a sufficient amount of filter aid. 3If the density exceeds this limit, the resin particles become too dense, and the fluidity necessary for the adsorbent to function is lost. The bulk density of the filter aid is 325 kg / m³. 3 Preferably, it should be 350 kg / m 3 It is more preferable that the amount be greater than or equal to 675 kg / m³. 3 Preferably, it is 650 kg / m 3 The following is more preferable: The filter aid has an appropriate bulk density, which improves the mixability and fluidity of the packing when packed into the adsorption column vessel together with the adsorbent.

[0029] Thus, the filter aid made of PAS resin according to the present invention has an appropriate particle size distribution and bulk density, so when packed into an adsorption column container together with the adsorbent, it is possible to obtain an adsorption column with excellent liquid permeability, mixability, and fluidity. Furthermore, if PAS resin (for example, porous PAS resin) is used as the adsorbent, the adsorbent and filter aid are made of the same type of resin, making it possible to easily recycle the adsorbent and filter aid that are the packing materials.

[0030] (Method of manufacturing a filtration aid) The method for producing a filtration aid according to the present invention includes a raw material resin preparation step, a compression step, a grinding step, and a sieving step, which will be described in detail below.

[0031] <Raw resin preparation process> First, in the raw material resin preparation process, a raw material PAS resin suitable for use as a filter aid is prepared by compression and pulverization, wherein the cumulative 90% particle size (D90) of the volume-based particle size distribution is 300 μm or less. From the viewpoint of handling, it is preferable that the cumulative 90% particle size is 95 μm or less, and more preferably 90 μm or less. In order to make it recyclable together with the porous PAS resin used as an adsorbent when used in an adsorption column, it is preferable that the raw material resin is free of other components other than PAS resin (except for unavoidable components derived from the polymerization reaction of PAS and water), such as surfactants (dispersants), colorants, antistatic agents, antioxidants, heat stabilizers, UV stabilizers, UV absorbers, foaming agents, flame retardants, flame retardant aids, rust inhibitors, mold release agents, and coupling agents.

[0032] <Compression process> In the compression process, the raw PAS resin prepared in the raw material resin preparation process is compressed at a temperature of 25°C to 80°C to obtain compressed PAS resin. By pre-compressing the resin before pulverizing it, the density of the compressed powder (compressed powder) increases, improving the fluidity of the particles after pulverization and increasing the bulk density. Therefore, if the resin temperature is lower than 25°C, the resin is hard and will be pulverized without being sufficiently compressed, while if it is higher than 80°C, the resin itself will soften and melt and deform without being compressed. It is preferable to compress the resin at a temperature of 27°C or higher, more preferably at 30°C or higher, and more preferably at 75°C or lower, and more preferably at 70°C or lower. The raw material resin can be efficiently compressed by processing it at an appropriate temperature below its glass transition temperature (Tg). Any method such as a roll press or hot press can be used for compression, and it is preferable to use a roll-type compression granulator.

[0033] <Grinding process> In the crushing process, the compressed PAS resin obtained in the compression process is crushed using a crusher to obtain crushed PAS resin. Any method such as a roll mill, hammer mill, or pin mill can be used for crushing, and it is preferable to use a roll-type compression granulator. From the viewpoint of efficiency, the crushing process may be carried out continuously with the compression process that precedes it.

[0034] <Sieving process> In the sieving process, the pulverized PAS resin obtained in the grinding process is classified, and pulverized PAS resin particles with a cumulative 90% particle size (D90) of 1 mm or less based on volume are recovered. If particles with a cumulative 90% particle size (D90) larger than 1 mm are used, a dense layer will be formed between the coarse and fine particles, making it impossible to ensure adequate water permeability for the adsorption column. The cumulative 90% particle size (D90) of the recovered pulverized PAS resin particles is preferably 950 μm or less, and more preferably 900 μm or less. Any method can be used for sieving, but from the viewpoint of efficiency, it is preferable to use a vibrating sieve. By keeping the recovered particle size within this range, the recovered pulverized PAS resin particles can be used as a filter aid. When this filter aid is packed into the adsorption column container together with the adsorbent, it can form appropriate voids between the adsorbent particles.

[0035] Furthermore, the filtration method using a filter material containing the filtration aid obtained in this way exhibits excellent liquid permeability, thereby increasing the processing speed of the solution. In addition, when PAS resin is used as the adsorbent, the filtration aid consisting of PAS resin particles is recyclable. Therefore, the above-described filtration method can be suitably used as a method for recovering precious metals from waste liquids such as industrial catalysts and metal plating solutions.

[0036] (Adsorption column) The adsorption column 100 according to the present invention is an adsorption column in which a column container 1 is packed with a packing material containing a filter aid 2 and a porous PAS resin 3, and will be described in detail below with reference to Figure 1.

[0037] <Column container> The column container 1 can be filled with porous PAS resin and a filter aid as filter material, and it is sufficient that a liquid can be passed through the filled filter material. For example, a cylindrical column with an internal volume of 1 L to 10 L can be used. In addition, while metal, resin, and glass can be used as materials, a polyvinyl chloride container is preferred from the viewpoint of being less affected by the properties of the liquid being passed through.

[0038] <Porous PAS resin> The porous PAS resin used to fill the column vessel has a specific surface area of ​​1 m². 2 / g or more 300m 2 Use resins with a specific surface area of ​​1 m² or less. 2 If the value is smaller than / g, it will not be able to adsorb enough of the metal that should be adsorbed, while 300m 2 If the value is greater than / g, the resin itself cannot maintain its structure. Porous PAS resin has a specific surface area of ​​10m². 2 It is preferable to use a material of 1 / g or more, 50m 2 It is more preferable to use one that is 250m or more. 2 It is preferable to use a product of less than / g, 200m 2 It is more preferable to use a material with a specific surface area of ​​less than / g. By setting the specific surface area of ​​the porous PAS resin used as an adsorbent to this range, the contact area between the porous PAS resin and the solution is increased when the solution is passed through the adsorption column, resulting in an adsorption column with excellent adsorption capacity.

[0039] Furthermore, the porous PAS resin used has a cumulative 50% particle size (D50) of 10 μm or more based on the volume-based particle size distribution. If the particle size is less than 10 μm, when the porous PAS resin is packed into the adsorption column, the column container will be excessively densely packed with the porous PAS resin, resulting in poor liquid permeability of the adsorption column. Preferably, the cumulative 50% particle size (D50) of the volume-based particle size distribution of the porous PAS resin is 20 μm or more, and more preferably 30 μm or more. By setting the particle size of the resin within this range, an adsorption column with superior liquid permeability can be obtained when packed into the adsorption column container together with a filter aid.

[0040] Furthermore, the porous PAS resin has a bulk density of 700 kg / m³. 3 The following resin will be used. Similar to the particle size, the bulk density will be 700 kg / m³. 3 If the density exceeds this limit, the porous PAS resin will be excessively densely packed into the column vessel, preventing the adsorption column from maintaining its liquid permeability when filled with porous PAS resin. The bulk density of porous PAS resin is 675 kg / m³. 3 Preferably, it is 650 kg / m 3 The following is more preferable: By setting the bulk density of the resin within this range, when it is packed into the adsorption column container together with the filter aid, it becomes easier to mix and flow, thus enabling the production of an adsorption column with excellent liquid permeability.

[0041] The method for producing the porous PAS resin described above is not particularly limited, but an example of a method for obtaining the porous PAS resin described above is explained below. For example, the porous PAS resin described above can be obtained by the following steps: (1) reacting a polyhalo-aromatic compound with (i) an alkali metal sulfide, or (ii) an alkali metal hydroxide and an alkali metal hydroxide in an organic polar solvent to obtain a crude reaction mixture containing at least PAS resin, an alkali metal halide, and an organic polar solvent; (2) removing the liquid phase component from the crude reaction mixture by solid-liquid separation to obtain a mixture (A) containing at least PAS resin and an alkali metal halide; and (3) washing the mixture (A) to remove the alkali metal halide and obtain the PAS resin. The steps in this example will be explained in detail below.

[0042] ·Process (1) Step (1) is a step in which a polyhalo-aromatic compound is reacted with (i) an alkali metal sulfide or (ii) an alkali metal hydroxide and an alkali metal hydroxide in an organic polar solvent (a) to obtain a crude reaction mixture containing at least a PAS resin, an alkali metal halide and an organic polar solvent (a).

[0043] In this example, the polyhalo-aromatic compound is, for example, a halogenated aromatic compound having two or more halogen atoms directly bonded to an aromatic ring. Specifically, examples include dihalo-aromatic compounds such as p-dichlorobenzene, o-dichlorobenzene, m-dichlorobenzene, trichlorobenzene, tetrachlorobenzene, dibrombenzene, diiodobenzene, tribrombenzene, dibromnaphthalene, triiodobenzene, dichlorodiphenylbenzene, dibromdiphenylbenzene, dichlorobenzophenone, dibrombenzophenone, dichlorodiphenyl ether, dibromdiphenyl ether, dichlorodiphenyl sulfide, dibromdiphenyl sulfide, dichlorobiphenyl, and dibrombiphenyl, as well as mixtures thereof. These compounds may also be block copolymerized. Among these, dihalogenated benzenes are preferred, and those containing 80 mol% or more of p-dichlorobenzene are particularly preferred.

[0044] In this example, alkali metal sulfides or alkali hydrosulfides and alkali metal hydroxides (hereinafter sometimes referred to as sulfidating agents) are used as raw materials.

[0045] In this example, the alkali metal sulfides include lithium sulfide, sodium sulfide, rubidium sulfide, cesium sulfide, and mixtures thereof. Such alkali metal sulfides can be used as hydrates, aqueous mixtures, or anhydrous forms. Alkali metal sulfides can also be obtained by the reaction of alkali metal hydroxides with alkali metal hydroxides. In addition, it is acceptable to add a small amount of alkali metal hydroxide to react with the alkali metal hydroxides and alkali metal thiosulfates that are usually present in trace amounts in the alkali metal sulfides.

[0046] Furthermore, the alkali metal hydrosulfides include lithium hydrogen sulfide, sodium hydrogen sulfide, rubidium hydrogen sulfide, cesium hydrogen sulfide, and mixtures thereof. Such alkali metal hydrosulfides can be used as hydrates, aqueous mixtures, or anhydrous products.

[0047] Furthermore, the alkali metal hydroxide is used together with an alkali metal hydroxide. Examples of alkali metal hydroxides include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, and cesium hydroxide, which may be used individually or in combination of two or more. Among these, lithium hydroxide, sodium hydroxide, and potassium hydroxide are preferred due to their availability, with sodium hydroxide being particularly preferred.

[0048] In the present example of the method for producing PAS resin, a hydrated sulfidating agent may be used as a raw material. In this case, it is preferable to dehydrate the hydrated sulfidating agent in the presence of at least an aprotic polar solvent before subjecting it to the polymerization reaction of the PAS resin. Furthermore, if the amount of aprotic polar solvent charged is small, for example, less than 1 mole per mole of sulfur atoms in the sulfidating agent, it is preferable to dehydrate the hydrated sulfidating agent and the aprotic polar solvent in the presence of a polyhalo-aromatic compound.

[0049] The dehydration step of the hydrated sulfidating agent is carried out by charging at least an aprotic polar solvent and a hydrated alkali metal sulfide or hydrated alkaline aqueous sulfide and alkali metal hydroxide as the hydrated sulfidating agent into a reaction vessel equipped with a distillation apparatus, heating to a temperature at which water is removed by azeotropy, specifically in the range of 300°C or less, preferably in the range of 80 to 220°C, more preferably in the range of 100 to 200°C, and then discharging the water from the system by distillation. In the dehydration step, it is preferable to dehydrate until the amount of water in the system carrying out the polymerization reaction is 5 moles or less, more preferably in the range of 0.01 to 2.0 moles, per mole of sulfur atoms of the sulfidating agent.

[0050] In this example, examples of organic polar solvents (a) include amides, ureas and lactams such as formamide, acetamide, N-methylformamide, N,N-dimethylacetamide, tetramethylurea, N-methyl-2-pyrrolidone, 2-pyrrolidone, N-methyl-ε-caprolactam, ε-caprolactam, hexamethylphosphoramide, N-dimethylpropyleneurea, and 1,3-dimethyl-2-imidazolidinonic acid; sulfolanes such as sulfolane and dimethylsulfolane; nitriles such as benzonitrile; ketones such as methylphenyl ketone and mixtures thereof. Among these, amides having an aliphatic cyclic structure such as N-methyl-2-pyrrolidone, 2-pyrrolidone, N-methyl-ε-caprolactam, ε-caprolactam, hexamethylphosphoramide, N-dimethylpropyleneurea, and 1,3-dimethyl-2-imidazolidinonic acid are preferred, and N-methyl-2-pyrrolidone is even more preferred.

[0051] In the PAS polymerization process, the polymerization reaction of the PAS resin involves reacting the alkali metal sulfide as a sulfidating agent with a polyhalo-aromatic compound in the presence of these organic polar solvents (a). Alternatively, the polymerization reaction of the PAS resin involves reacting the alkali metal hydroxide and alkali metal hydroxide as sulfidating agents with a polyhalo-aromatic compound in the presence of these aprotic polar solvents. The polymerization conditions are generally in the temperature range of 200 to 330°C, and the pressure should be in a range that substantially maintains the polymerization solvent and the polyhalo-aromatic compound, which is the polymerization monomer, in the liquid phase, and is generally selected from the range of 0.1 to 20 MPa, preferably from 0.1 to 2 MPa. The amount of polyhalo-aromatic compound to be charged is prepared in the range of 0.2 moles to 5.0 moles, preferably from 0.8 to 1.3 moles, and more preferably from 0.9 to 1.1 moles, per mole of sulfur atoms of the sulfidating agent. Furthermore, the amount of aprotic polar solvent charged should be adjusted to a range of 1.0 to 6.0 moles, preferably 2.5 to 4.5 moles, per mole of sulfur atoms of the sulfidating agent. The polymerization reaction is preferably carried out in the presence of a small amount of water, and the proportion should be appropriately adjusted in consideration of the polymerization method, the molecular weight of the resulting polymer, and productivity. Specifically, the dehydration operation should be carried out to a range of 2.0 moles or less, preferably 1.6 moles or less, per mole of sulfur atoms of the sulfidating agent. However, if the dehydration operation is carried out in the presence of a polyhalo-aromatic compound (for example, the method in "5)" in the specific embodiment below), the dehydration operation should be carried out to a range of 0.9 moles or less, preferably 0.05 to 0.3 moles, more preferably 0.01 to 0.02 moles or less.

[0052] Specific embodiments of polymerizing a sulfidating agent and a polyhalo-aromatic compound in the presence of the above-mentioned organic polar solvent (a) include, for example, 1) A method using polymerization aids such as alkali metal carboxylates or lithium halides. 2) A method using branching agents such as aromatic polyhalogen compounds, 3) A method in which polymerization is carried out in the presence of a small amount of water, and then water is added to further polymerize the molecule. 4) A method in which, during the reaction of an alkali metal sulfide with an aromatic dihalogen compound, the gas phase portion of the reaction vessel is cooled to condense a portion of the gas phase inside the reaction vessel and reflux it into the liquid phase. 5) A method for producing PAS resin, which includes the essential steps of: producing a slurry containing solid alkali metal sulfide by reacting an alkali metal sulfide, or a hydrated alkali metal hydroxide and alkali metal hydroxide, with an amide, urea, or lactam having an aliphatic cyclic structure while dehydrating it in the presence of a polyhalo-aromatic compound; after producing the slurry, further adding a polar organic solvent such as NMP (N-methyl-2-pyrrolidone) and removing the water by distillation to dehydrate it; and then, in the slurry obtained after the dehydration step, polymerizing by reacting a polyhalo-aromatic compound, an alkali metal hydroxide, and an alkali metal salt of the hydrolysis product of the amide, urea, or lactam having an aliphatic cyclic structure, at a rate of 0.02 moles or less of water present in the reaction system per mole of a polar organic solvent such as NMP.

[0053] Thus, by polymerizing a dihalo-aromatic compound with (i) an alkali metal sulfide, or (ii) an alkali metal hydroxide and an alkali metal hydroxide in an organic polar solvent (a), a PAS resin is obtained as a product, but cyclic PAS oligomers are also produced as by-products. Substances contained after the reaction may also include by-products such as alkali metal-containing inorganic salts, carboxyalkylamino group-containing compounds, and terminal SH group-containing compounds, as well as unreacted raw materials and water. In particular, it is thought that if the crude reaction mixture contains an alkali metal halide as an essential component, it will contribute to improving the specific surface area of ​​the obtained PAS resin. That is, it is thought that alkali metal halides are incorporated when the PAS resin aggregates in the poor solvent in step (2), and then the alkali metal halides are removed by washing in the subsequent step (3), resulting in porosity.

[0054] ·Process (2) Step (2) is a step of removing the liquid phase component from the crude reaction mixture by solid-liquid separation to obtain a mixture (A) containing at least PAS resin and alkali metal halide.

[0055] There are two main types of solid-liquid separation: the flash method and the quench method, which will be described later. Both can be used in this process. The flash method is a method of recovering the solvent by evaporating it from the crude reaction mixture, and simultaneously recovering the solid material. Generally, it is a method in which the crude reaction mixture is flashed from a high-temperature, high-pressure state to an atmosphere of normal pressure or reduced pressure, and the solvent is removed and recovered while the solid material containing the PAS resin is recovered in powder form. A preferred embodiment of the flash method is a method in which the polymer reaction product obtained in the polymerization process at high temperature and high pressure (usually 240°C or higher, 0.3 MPa or higher) is ejected from a nozzle into an atmosphere of nitrogen or water vapor at normal pressure. In the flash method, the solvent can be efficiently recovered by utilizing the heat of vaporization of the solvent when the polymer reaction product is flashed from a high-temperature, high-pressure state to a normal pressure state. However, it is preferable to keep the internal temperature low during flashing so that the surface of the PAS resin remains wet, from the viewpoint of excellent adsorption performance at the start of use. Therefore, the temperature and pressure within the polymerization system during flashing are typically set to a temperature range of 240°C or higher, preferably 250-280°C, and a pressure range of 0.3 MPa or higher, preferably 0.4-5.0 MPa. When flashing from this state under reduced pressure or atmospheric pressure, the ambient temperature is typically in the range of 25°C or higher and 150°C or lower.

[0056] On the other hand, the Quench method is a method for recovering particulate PAS resin by slowly cooling the crude reaction mixture. Generally, the crude reaction mixture is gradually cooled from a high-temperature, high-pressure state to crystallize the PAS resin in the reaction system, and then the solid component containing the PAS resin is recovered as granules by solid-liquid separation using filtration or the like. There are no particular restrictions on the cooling time, but it is usually in the range of 0.1°C / min to 5°C / min. Furthermore, it is not necessary to cool at the same rate throughout the entire slow cooling process. It is also preferable to cool at a rate of 0.1°C / min to 1°C / min until the granular PAS resin crystallizes, and then at a rate of 1°C / min or higher. Finally, it is preferable to cool to 70°C or higher, preferably 100°C or higher and 200°C or lower, and then recover the solid component containing the PAS resin by solid-liquid separation. Solid-liquid separation in the Quench method can be achieved using filtration or a centrifuge such as a screw decanter.

[0057] ·Process (3) Step (3) is a step of washing the mixture (A) to remove alkali metal halides.

[0058] In this process, the mixture (A) is washed by washing with water. After washing with water, methods for solid-liquid separation include, for example, adding water to the slurry and stirring, then filtering using a filtration device; adding water again to the water-containing filtration residue obtained by the above filtration (hereinafter abbreviated as "hydrated cake") to form a slurry, and then filtering; or adding water again while the hydrated cake is held in the filter and then filtering.

[0059] During the aforementioned washing, the amount of water added to the mixture (A) is preferably in the range of 2 to 20 times the theoretical yield of the PAS resin that will ultimately be obtained, from the viewpoint of washing efficiency. It is preferable to divide the above amount of water into 1 to 10 washes, preferably 1 to 4 washes. The washing is preferably carried out under a nitrogen or air atmosphere at a water temperature in the range of 20°C to 80°C, more preferably in the range of 25°C to 75°C, and most preferably in the range of 30°C to 70°C. The washing can be repeated once or multiple times. When washing is repeated multiple times, the atmosphere and temperature conditions may be the same or different.

[0060] Furthermore, in order to make it recyclable together with the PAS resin used as a filter aid, it is preferable that the porous PAS resin is free from other components other than the PAS resin (except for unavoidable components derived from the polymerization reaction of PAS and water), such as known and conventional additives like surfactants (dispersants), colorants, antistatic agents, antioxidants, heat stabilizers, UV stabilizers, UV absorbers, foaming agents, flame retardants, flame retardant aids, rust inhibitors, mold release agents, and coupling agents.

[0061] <Mixing ratio> Furthermore, the mixing ratio of the filter aid and porous PAS resin in the packing material is 1:99 or more and 50:50 or less (parts by mass). If the proportion of the filter aid is less than 1 part by mass, the liquid permeability of the packing material is poor, and if it exceeds 50 parts by mass, the proportion of porous PAS resin, which acts as an adsorbent contributing to metal adsorption, decreases, and sufficient adsorption capacity cannot be obtained. The mixing ratio of the filter aid and porous PAS resin in the packing material is preferably 5:95 or more, more preferably 10:90 or more, preferably 45:55 or less, and more preferably 40:60 or less. By setting the mixing ratio of the porous PAS resin, which is the adsorbent, and the filter aid, which forms appropriate voids between them, within this range in the adsorption column container, an adsorption column with excellent liquid permeability and excellent solution processing speed under low pressure conditions can be obtained.

[0062] <Filling rate> Furthermore, the packing density of the packing material in the column container filled with the above proportions is 0.05 or more and 0.3 or less. If the packing density is less than 0.05, the absolute amount of porous PAS resin as an adsorbent in the column container is small, and the adsorption column will not exhibit sufficient adsorption capacity. If the packing density exceeds 0.3, the liquid permeability of the adsorption column cannot be ensured. The packing density of the packing material in the column container is preferably 0.07 or more, more preferably 0.10 or more, preferably 0.28 or less, and more preferably 0.25 or less. By setting the packing density of the packing material in the column container within this range, an adsorption column with excellent liquid permeability and excellent solution processing speed under low-pressure conditions can be obtained.

[0063] The adsorption column according to the present invention is obtained by filling a column vessel with a porous PAS resin having an appropriate specific surface area, particle size distribution, and bulk density, and a filter aid consisting of PAS resin particles having an appropriate particle size distribution and bulk density, in an appropriate ratio, thereby providing an adsorption column with excellent liquid permeability and adsorption capacity, and in which the packing material can be easily recycled.

[0064] (Method for manufacturing adsorption columns) The method for manufacturing the adsorption column 100 according to the present invention includes a filling step of filling a column container 1 with packing material and a compression step of compressing the packing material, and the details are described below.

[0065] <Filling process> First, in the packing process, a packing material containing a filter aid 2 and porous PAS resin 3 is packed into the column container 1 on top of a filter 5 for preventing leakage. The shape of the column container 1 is not limited, but it has an inlet 20 and an outlet 30 that allow liquid to pass through the packing material, and for example, a cylindrical column with an internal volume of 1 to 10 L can be used. In addition, although metal, resin and glass can be used as materials, a polyvinyl chloride container is preferred from the viewpoint of being less affected by the properties of the liquid being passed through. The filter aid and porous PAS resin in the packing material are packed in a ratio of 1:99 to 50:50 (parts by mass). The mixing ratio of the filter aid and porous PAS resin in the packing material is preferably 5:95 or higher, more preferably 10:90 or higher, preferably 45:55 or lower, and more preferably 40:60 or lower.

[0066] In this embodiment, the method of packing the column is not particularly limited, and known methods can be used. For example, methods include packing the filter aid and porous PAS resin directly, dispersing the filter aid and porous PAS resin in a suitable liquid medium, such as water, to form a slurry, and then packing this slurry into the column container (body feed method), or forming a cake layer of porous PAS resin, which is the adsorbent, first, and then forming the filter aid on top of it (pre-coat method).

[0067] <Filling Compression Process> In the packing compression process, the bulk density of the packing material is 400 kg / m³. 3 More than 600kg / m 3 Compress until the following is achieved. By keeping the bulk density within this range, the packing material can be made to have excellent mixability, fluidity, and liquid permeability. The bulk density of the packing material is 425 kg / m³. 3 Preferably, it should be 450 kg / m 3 It is more preferable to set it to 575 kg / m 3 The following is preferable: 550 kg / m 3 The following is more preferable.

[0068] Any method can be used to compress the packing material, but since a solvent can be introduced into the packing material by gas pressure or pump pressure to compact it, a method using water compression is preferred from the viewpoint of simplicity.

[0069] The adsorption column 100 exhibits excellent adsorption properties due to the use of porous PAS resin, and also has excellent liquid permeability when combined with an appropriate filter aid, thereby enabling a high rate of solution processing. Furthermore, since both the porous PAS resin used as the adsorbent and the PAS resin used as the filter aid are made of PAS resin, the packing material of the adsorption column 100 can be easily recycled. The adsorption column 100 thus obtained allows for the separation and recovery of metals and / or metal ions in a solution by introducing a solution containing metals and / or metal ions from the inlet 10 and recovering only the solution after the metals and / or metal ions have been desorbed from the outlet 20. [Examples]

[0070] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Also, "%" in the compositions of the following examples means "mass %".

[0071] 1. Measurement or evaluation methods used in the examples and comparative examples. The filtration aids and adsorption columns obtained in the examples and comparative examples described below were evaluated using the following test methods.

[0072] (Bulk density) PPS resin was poured into a 100 mL stainless steel cylindrical container with a closed bottom (inner diameter 50.46 mm x depth 50 mm) using a spatula until it overflowed. After leveling off the excess PPS resin, its weight was measured to the nearest 0.01 g. The number average of three weight measurements was divided by the internal volume of the cylindrical container to determine the bulk density (kg / m³). 3 ) was calculated as follows.

[0073] (specific surface area) The specific surface area was measured using the "Tristar II 3020" manufactured by Shimadzu Corporation. The PPS resin obtained in each example and comparative example was pretreated by standing at 60°C under vacuum for 4 hours, then placed in the measurement cell, degassed, and replaced with helium. The specific surface area of ​​the resin was then measured by cooling to -196°C and replacing with nitrogen.

[0074] (particle size distribution) The particle size distribution of the PPS resin obtained in each example and comparative example was measured using a laser diffraction scattering particle size distribution analyzer (Microtrac MT3300EXII) in accordance with the laser diffraction and scattering method (JIS Z8825). D90, D50, and D10 were calculated from the obtained particle size distributions.

[0075] (Pressure before column) In each example and comparative example, the undried PPS resin (non-volatile content 40.0%) was packed into a 3.9 L (100 mm inner diameter x 500 mm height) cylindrical column made of polyvinyl chloride, with 1.96 kg of PAS resin added, and water was added to it at SV=10h. -1 The flow rate was adjusted to achieve the desired result, and the liquid was allowed to pass through. The pump's discharge pressure (pressure in the liquid flow line) was measured 10 minutes after the liquid had been passed through using a pressure gauge placed in front of the column.

[0076] The non-volatile content was calculated from the weight of 5,000 g of the PPS resin obtained in each example and comparative example before drying, after drying in a hot air dryer at 120°C for 4 hours. Non-volatile content (%) = Weight after drying ÷ Weight before drying × 100

[0077] (Filling rate) In each example and comparative example, the bulk volume of the packing material was calculated from the height of the packing material inside the column container 10 minutes after liquid flow was measured in the column. Then, the packing density, obtained by multiplying the number average of three measurements of the packing weight by the non-volatile content, was divided by the bulk volume, and further divided by the true density of the packing material to calculate the packing efficiency. At this time, the true specific gravity of PPS was 1350 kg / m³. 3 Radiolite has a load capacity of 2200 kg / m³. 3 Water is 1000 kg / m³3 It was calculated as follows.

[0078] (Palladium capture rate) The PPS resin obtained in each example and comparative example, before drying, was subjected to a palladium solution at a rate of 0.67 L / min (SV=10h) of 500 kg, where the palladium concentration (C0) before adsorption was 100 ppm. -1 The solution was supplied at a flow rate of ), and the concentration of palladium (C) in the solution that passed through the packing material was quantified using an atomic absorption spectrophotometer. The adsorption rate (%) expressed by the following formula was calculated using the solution concentration before adsorption (C0) and the solution concentration after adsorption (C), and a rate of 60% or more was expressed as "high," and a rate of less than 60% was expressed as "low." Adsorption rate (%)=(C0-C) / C0×100

[0079] 2. Filtration aids The filter aid PAS, consisting of PPS resin particles, used in the examples and comparative examples was prepared as follows.

[0080] (2-1) Raw resin preparation process First, in the raw material preparation process for the filter aid, the raw material PPS resin can be prepared as follows.

[0081] ·Process (4) A 100L autoclave equipped with a stirring blade and connected to a pressure gauge, thermometer, condenser, decanter, and rectification column was charged with 24.402 kg (166 mol) of DCB (p-dichlorobenzene; hereinafter abbreviated as DCB), 2.696 kg (16 mol) of NMP, 20.178 kg (170 mol) of 47.23% NaSH aqueous solution, and 13.574 kg (167 mol) of 49.21% NaOH aqueous solution. The mixture was heated to 173°C over 5 hours under a nitrogen atmosphere while stirring, and 20.059 kg of water was distilled off, after which the autoclave was sealed. The DCB distilled off by azeotrope during dehydration was separated in the decanter and returned to the autoclave as needed. After dehydration, the contents of the autoclave were in a state where anhydrous sodium sulfide composition was dispersed in DCB. After the above dehydration process was completed, the internal temperature was cooled to 160°C, 34.092 kg (340 mol) of NMP was charged, and the temperature was raised to 185°C. When the pressure reached 0.00 MPa, the valve connected to the rectification column was opened, and the internal temperature was raised to 200°C over 1 hour. During this time, the temperature at the outlet of the rectification column was controlled by cooling and valve opening to keep it below 110°C. The distilled DCB and water mixture vapor was condensed in a condenser, separated in a decanter, and the DCB was returned to the vessel. The amount of water distilled was 132 g. The internal temperature was raised from 200°C to 230°C over 3 hours, stirred for 3 hours, and then raised to 250°C and stirred for 1 hour.

[0082] The crude reaction mixture obtained in step (4) was flushed into a 150L vacuum stirring dryer equipped with stirring blades, and the mixture was dried under vacuum at 150°C for 4 hours, after which the NMP was removed and the mixture was cooled to room temperature. A crude PPS mixture with a solid content of 99.5% was obtained.

[0083] 9 kg of the obtained crude PPS mixture was mixed with 54 kg of ion-exchanged water at 70°C and stirred for 30 minutes, then filtered. 90 kg of ion-exchanged water at 70°C was added to the filtered cake to wash it. Furthermore, the resulting water-containing cake and 54 kg of ion-exchanged water were placed in a 70 L autoclave equipped with stirring blades. The temperature was raised to 230°C over 2 hours while stirring, and the mixture was stirred for 30 minutes to perform the extraction process. The mixture was then cooled to room temperature. The entire resulting mixture was filtered, and 90 kg of ion-exchanged water at 70°C was added to the filtered cake to wash it and obtain the desired raw material PPS resin.

[0084] When the volume-based particle size distribution of these resins was measured, the cumulative 90% particle size (D90), cumulative 50% particle size (D50), and cumulative 10% particle size (D10) were 200 μm, 30 μm, and 10 μm, respectively.

[0085] (2-2) Compression process and grinding process Next, the raw PPS resin prepared in the raw material preparation process was compressed and pulverized using a roller compactor (Freund Turbo Co., Ltd., Model: FT105) in an atmosphere of 30°C to obtain pulverized PPS resin.

[0086] (2-3) Sieving process The crushed PPS resin obtained in the compression and crushing processes was then sieved using a circular vibrating sieve (Kowa Kogyosho Co., Ltd., Model: KF-700). Sieves with mesh sizes of 1 mm, 100 μm, and 30 μm were used. PPS resin particles that passed through the 1 mm sieve and were sieved onto the 100 μm sieve (classified as 100 μm to 1 mm) were designated as filter aid PAS-1. Similarly, PPS resin particles classified as 30 μm to 100 μm were designated as filter aid PAS-2, and PPS resin particles classified as 30 μm or less were designated as filter aid PAS-3. The PPS resin particles remaining on the 1 mm sieve were designated as filter aid PAS-4. The particle size of these classified filter aids was measured.

[0087] 3. Adsorption column

[0088] Next, an adsorption column was prepared using the above-mentioned filter aid PAS and porous PAS resin.

[0089] (Porous PAS resin) The porous PAS resin to be packed into the column vessel was prepared as follows.

[0090] ·Process (5) A 100L autoclave equipped with stirring blades, connected to a pressure gauge, thermometer, condenser, decanter, and rectification column, was charged with 24.402 kg (166 mol) of DCB, 2.696 kg (16 mol) of NMP, 20.178 kg (170 mol) of 47.23% NaSH aqueous solution, and 13.574 kg (167 mol) of 49.21% NaOH aqueous solution. The mixture was heated to 173°C over 5 hours under a nitrogen atmosphere with stirring, and 20.059 kg of water was distilled off, after which the autoclave was sealed. The DCB distilled off by azeotrope during dehydration was separated in the decanter and returned to the autoclave as it was removed. After dehydration, the autoclave contained an anhydrous sodium sulfide composition dispersed in the DCB. After the above dehydration process was completed, the internal temperature was cooled to 160°C, 34.092 kg (340 mol) of NMP was charged, and the temperature was raised to 185°C. When the pressure reached 0.00 MPa, the valve connected to the rectification column was opened, and the internal temperature was raised to 200°C over 1 hour. During this time, the temperature at the outlet of the rectification column was controlled by cooling and valve opening to keep it below 110°C. The distilled DCB and water mixture vapor was condensed in a condenser, separated in a decanter, and the DCB was returned to the vessel. The amount of water distilled was 132 g. The internal temperature was raised from 200°C to 230°C over 3 hours, stirred for 3 hours, and then raised to 250°C and stirred for 1 hour.

[0091] The crude reaction mixture obtained in step (5) was flushed into a 150 L vacuum stirring dryer equipped with stirring blades and cooled to room temperature. A crude PPS mixture with a solid content of 45% was obtained.

[0092] 18 kg of the obtained crude PPS mixture was mixed with 54 kg of ion-exchanged water at 30°C for 30 minutes and then filtered. 90 kg of ion-exchanged water at 30°C was added to the filtered cake to wash it. This procedure was repeated two more times to obtain porous PPS resin, specifically porous PAS resin PAS-1.

[0093] Similarly, by taking the crude reaction mixture obtained in step (5) into a mixed solution (10% water, 90% NMP) in 180 L over 12 minutes, which was kept warm at 40°C under atmospheric pressure, porous PAS resin PAS-2 was obtained as a porous PPS resin.

[0094] The bulk density, specific surface area, and particle size distribution of the filter aid PAS and porous PAS resin used in the examples and comparative examples prepared in this manner were measured. The results of each evaluation are shown in Table 1 below.

[0095] [Table 1]

[0096] (3-1) Filling process The resulting filter aid PAS and porous PAS resin were mixed in the proportions shown in Table 2 and filled into a cylindrical polyvinyl chloride container with a diameter of 100 mm, a length of 500 mm, and a volume of 3.9 L.

[0097] (3-2) Filling Compression Process Then, by passing water through the column, the compression density of the packing material becomes 400 kg / m³, after the filter aid PAS and porous PAS resin have been packed into the column vessel in a predetermined mass ratio. 3 More than 600kg / m 3 It was compressed until it was as follows:

[0098] (Examples 1-6 and Comparative Examples 1-5) Table 2 shows the manufacturing conditions and measurement results for the adsorption columns related to the Reference Example, Examples 1-6 and Comparative Examples 1-5, which were manufactured as described above. Here, "A" in the supply method means that the column was filled by the body feed method, and "B" means that the column was filled with porous PAS resin by the pre-coat method, followed by filling with a filter aid made of PPS resin.

[0099] Furthermore, the recycling of the filter aid PAS and porous PAS resin obtained in the examples and comparative examples was confirmed as follows.

[0100] ·Process(6) An adsorbent from which palladium had been removed using a 1% thiourea solution, a filter aid (which may contain water or be dried and dehydrated), and NMP in an amount four times the amount of nonvolatile components were placed in a 100L autoclave equipped with a stirring blade and connected to a pressure gauge and thermometer. The autoclave was heated to 250°C over 6 hours under a nitrogen atmosphere while stirring, and then stirred for 1 hour.

[0101] The crude reaction mixture obtained in step (6) was flushed into a 150L vacuum stirring dryer equipped with stirring blades, and the mixture was dried under vacuum at 150°C for 4 hours, after which the NMP was removed and the mixture was cooled to room temperature. A crude PPS mixture with a solid content of 99.5% was obtained.

[0102] To the obtained crude PPS mixture, six times the volume of ion-exchanged water at 30°C was added and the mixture was stirred for 30 minutes, then filtered. After filtering, six times the volume of ion-exchanged water at 30°C was added to the cake to wash it. This procedure was repeated twice.

[0103] The specific surface area of ​​the obtained PPS resin was 150 m². 2 The particle size distribution based on volume was 200 μm, 30 μm, and 10 μm for the cumulative 90% particle size (D90), 50% particle size (D50), and 10% particle size (D10), respectively. The bulk density was 500 kg / m³. 3 This led to the acquisition of porous PAS resin. [Table 2]

[0104] From the results of the above examples, it was found that the adsorption column made solely of porous PAS resin in the reference example was unsuitable for practical use because it did not contain a filter aid, resulting in high column pressure and low liquid permeability. On the other hand, from the results of Examples 1 to 5, it was found that by using a filter aid PAS made of PAS resin with an appropriate particle size distribution in combination with porous PAS resin, an adsorption column was obtained that had low column pressure and excellent palladium capture capacity. Furthermore, when radiolite was used as a filter aid as in Comparative Example 1, there were no problems in terms of column pressure and palladium capture rate, but it was difficult to separate the adsorbent and the filter aid, making it impossible to easily recycle the packing material in the column. Also, even when PAS resin was used as a filter aid as in Comparative Example 2, when filter aid PAS-4 with particle sizes exceeding 1 mm for both D90 and D50 was used, the column pressure became high, and it was not possible to ensure adequate water permeability for the adsorption column. Furthermore, the results from Comparative Example 3 showed that while the recyclability of the filter aid and the column pressure were not problematic, if the proportion of the filter aid in the mixture of the filter aid and the porous PAS resin became too large, a sufficient palladium capture rate could not be obtained. This is thought to be due to a decrease in the amount of porous PAS resin that contributes to metal adsorption. Similarly, in Comparative Example 4, which used porous PAS resin PAS-2 with a low bulk density as the adsorbent, it was found that although the water permeability and packing efficiency could be improved by using a filter aid, a sufficient palladium capture rate could not be obtained. This is because the bulk density of the porous PAS resin PAS-2 itself is 200 kg / m³. 3 Because the value is low, it is thought that the packing efficiency of the packing material formed in the adsorption column when combined with a filter aid was low, and therefore sufficient adsorption capacity could not be obtained overall. [Industrial applicability]

[0105] According to the present invention, it is possible to provide a filter aid that, when used in an adsorption column, has liquid permeability that is at least as good as or better than that of the prior art. Furthermore, according to the present invention, when porous PAS resin is used as the adsorbent, it is possible to provide a filter aid that allows for easy recycling of the adsorbent packing and the filter aid. In addition, according to the present invention, it is possible to provide an adsorption column using the filter aid, a filtration method using a filter material containing the filter aid, a method for manufacturing an adsorption column using the filter aid, and a method for separating and recovering metals and / or metal ions using the adsorption column.

[0106] [Contribution to the United Nations-led Sustainable Development Goals (SDGs)] The SDGs have been proposed to realize a sustainable society. One embodiment of this invention is considered to be a technology that can contribute to "No. 7: Affordable and Clean Energy" and "No. 12: Responsible Consumption and Production," among others. [Explanation of Symbols]

[0107] 1 Column vessel 2. Filtration aids 3 Porous PAS resin 5 filters 10 Inlet 20 Outlet 100 adsorption columns

Claims

1. The cumulative 90% particle size (D90) of the volume-based particle size distribution is 1 mm or less, and the cumulative 50% particle size (D50) is 5 μm or more and 600 μm or less. Bulk density of 300 kg / m³ ３ More than 700kg / m ３ A filter aid consisting of polyarylene sulfide resin particles, as described below.

2. The filter aid according to claim 1, wherein the cumulative 90% particle size (D90) of the volume-based particle size distribution is 10 μm or more and 1 mm or less.

3. Column vessel and An adsorption column comprising a packing material packed into the column container, The aforementioned filler is (i) Specific surface area of ​​1 m ２ / g or more 300m ２ The particle size is less than or equal to / g, the cumulative 50% particle size (D50) of the volume-based particle size distribution is 10 μm or larger, and the bulk density is 700 kg / m³. ３ The following are porous polyarylene sulfide resins, (ii) comprising the filter aid described in claim 1, The mixing ratio of the filter aid and the porous polyarylene sulfide resin in the packing material is 1:99 or more and 50:50 or less (parts by mass), An adsorption column in which the packing density of the packing material is 0.05 or more and 0.3 or less.

4. A raw material resin preparation process for preparing a raw material polyarylene sulfide resin in which the cumulative 90% particle size (D90) of the volume-based particle size distribution is 300 μm or less, A compression step is performed to obtain compressed polyarylene sulfide resin by compressing the raw material polyarylene sulfide resin obtained in the raw material resin preparation step at a temperature of 25°C to 80°C. A crushing step is performed to obtain crushed polyarylene sulfide resin by crushing the compressed polyarylene sulfide resin obtained in the compression step using a crusher. A sieving step is performed to classify the pulverized polyarylene sulfide resin obtained in the pulverization step and recover pulverized polyarylene sulfide resin particles in which the cumulative 90% particle size (D90) of the volume-based particle size distribution is 1 mm or less. A method for producing a filtration aid containing a filtration aid.

5. Compressed polyarylene sulfide resin is obtained by compressing the aforementioned raw material polyarylene sulfide resin using a roll-type compression granulator. A method for producing a filtration aid according to claim 4.

6. The compressed polyarylene sulfide resin is crushed using a roll-type compression granulator to obtain pulverized polyarylene sulfide resin. A method for producing a filtration aid according to claim 4.

7. The pulverized polyarylene sulfide resin is sieved using a vibrating sieve to recover pulverized polyarylene sulfide resin particles in which the cumulative 90% particle size (D90) of the volume-based particle size distribution is 1 mm or less. A method for producing a filtration aid according to claim 4.

8. A packing step of packing a column vessel with a packing material comprising a filter aid manufactured by the method of claims 4 to 7 and a porous polyarylene sulfide resin, The packing step includes compressing the packing material packed into the column container in the packing step, In the filling step, the filter aid and the porous polyarylene sulfide resin in the filler are filled in a ratio of 1:99 or more and 50:50 or less (parts by mass). In the aforementioned packing compression step, the bulk density of the packing is 400 kg / m³. ３ More than 600kg / m ３ A method for manufacturing an adsorption column, which involves compressing it until it reaches the following limit.

9. The method for manufacturing an adsorption column according to claim 8, wherein the packing compression step is a step of compressing the packing in the column container by passing water through it.

10. A method for separating and recovering metals and / or metal ions in a solution, comprising separating and recovering metals and / or metal ions in an adsorption column obtained by the manufacturing method described in claim 8.

11. A filtration method using a filter material containing a filter aid obtained by the manufacturing method described in claim 4.

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