JP2002282711A - Apparatus and method for capturing ion by using powdery chelating/capturing material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and a method for capturing ions by using a powdery chelating/capturing material, by which a metallic ion or the ions of the metallic elements of the group similar to the metallic ion can efficiently be captured by using the powdery chelating/capturing material. SOLUTION: A plurality of ion capturing units each having a reaction means and a solid-liquid separating means are arranged in series so that the powdery chelating/capturing material discharged from the ion capturing unit at the preceding stage is regenerated and introduced into the ion capturing unit at the succeeding stage and the powdery chelating/capturing material discharged from the ion capturing unit at the succeeding stage is introduced into the ion capturing unit at the preceding stage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ion trapping treatment apparatus and method using a powdery chelate trapping material, and more particularly, to a metal ion or a class of metal (semimetal) contained in a liquid such as an aqueous liquid or an oily liquid. ) Ions, for example, heavy metal ions such as copper, zinc, nickel and cobalt, and harmful or valuable metal ions such as boron, germanium, arsenic, antimony, selenium, tellurium and other similar metal ions, metal compound ions and boric acid. It can efficiently remove ions containing metal-like elements such as ions, and purify various liquids such as water such as industrial drainage water, drinking water and food processing water, and oils such as edible oil and food processing oil. The present invention relates to an ion trapping treatment apparatus and method using a powdery chelate trapping material that can be used.

[0002]

2. Description of the Related Art Industrial effluents may contain various harmful metal ions or ions containing metal-like elements. From the viewpoint of environmental pollution prevention, these metal ions or ions containing metal-like elements are drained. It must be sufficiently removed by the treatment. Also, heavy metal components contained in rivers and groundwater have a bad effect on the human body. Therefore, careful consideration must be given to the effective use of these waters. In addition, metals that may be mixed as hydrogenation catalysts when producing edible oils or food processing oils, etc., have adverse effects on storage stability and the human body. is there.

[0003] In addition, boron and boron compounds, which are a kind of metalloid, are widely distributed in nature and are essential elements for the human body. On the other hand, it has also been confirmed that excessive intake leads to adverse effects. Have been. In addition, there are reported cases of human contamination due to boron components contained in rivers and groundwater, and there is a concern about adverse effects when water is reused. Furthermore, in addition to boron, for example, arsenic and arsenic compounds are harmful to the human body, and must be removed from drinking water or the like where contamination is concerned as much as possible.

[0004] On the other hand, conventionally, ion-exchange has been used to remove harmful metal ions or ions containing metal-like elements contained in wastewater or the like, or to capture ions containing valuable or valuable metal ions or metal-like elements. Although resins are widely used, the effect of selectively adsorbing and separating low-concentration metal ions or ions containing metal-like elements has not always been satisfactory.

[0005] A chelate resin having a property of selectively capturing a chelate by forming a chelate with a metal ion or an ion containing a metal-like element is an ion containing a metal ion or a metal-like element, particularly Since it has excellent selective capturing properties for heavy metal ions, it is used for removing and capturing heavy metals in the field of water treatment. However, most of the chelate resins simply have a chelate-forming functional group such as iminodiacetic acid introduced therein, and do not always show satisfactory chelate-forming ability.

Further, ordinary ion exchange resins and chelate-forming resins are in the form of beads having a rigid three-dimensional structure given by a crosslinking agent such as divinylbenzene, and contain metal ions or similar metal elements inside the resin. Since the diffusion rate of ions and regenerant is low, there is a problem in the processing efficiency. In addition, since water contains several tens of percent, it cannot be used as it is in non-aqueous liquids such as oil. In addition, if it is a type that is disposable without recycling, it is difficult to incinerate it,
A major issue is how to reduce the volume of used resin.

[0007] As a solution to the problem of such a bead-like chelating resin, a fibrous or sheet-like chelating agent has been proposed (see JP-A-7-10925). This fibrous or sheet-like chelating agent has a large specific surface area, and has a chelating-forming functional group on the surface which serves as a point of absorption and desorption of ions containing metal ions or metal-like elements, thereby increasing absorption and desorption efficiency. In addition, it has many advantages such as easy incineration. However, the fibrous or sheet-like chelating agent is complicated in its production method, and must employ a method using ionizing radiation.
Many practical problems have been pointed out in terms of manufacturing cost and the like. Further, although the ion adsorption speed of such a fibrous or sheet-like chelating agent is faster than that of the above-mentioned bead-like chelating resin, there is also a drawback that it is greatly affected by the fiber shape.

Further, when a solution is treated using a fibrous or sheet-form chelating agent, it is necessary to devise, for example, processing the chelating agent into a filter in order to bring the solution into efficient contact with the chelating agent. In addition, a fibrous or sheet-like chelating agent cannot be used as it is and can be easily utilized using existing equipment.

In order to solve these problems, a powdery chelate trapping material has been developed (JP-A-2000-1698).
No. 28). By using this powdery chelate trapping material, the surface area of the chelating material is dramatically increased, the reaction time can be greatly reduced, and the absorption / desorption efficiency of ions containing metal ions or metal-like elements increases, resulting in waste. Disposal also becomes easier.

[0010]

In the above-described apparatus for removing metal ions or ions containing metal-like elements by using a chelating agent as described above, in a conventional apparatus using a bead-type chelating resin, a filling type reaction apparatus is used. And the step of adsorbing metal ions or ions containing metal-like elements and the step of desorbing and regenerating are alternately performed in the same reactor. For this reason, when the chelate resin is being regenerated in the desorption regeneration step, it becomes impossible to perform adsorption treatment of metal ions or ions containing metal-like elements, so that the adsorption step is performed alternately by installing a plurality of the same reactors. They need to be operated, leading to high initial equipment costs. In addition, when a powdery chelate trapping material is used, a conventional packed-type reactor causes outflow of the material, so that it is necessary to develop a new reactor.

Therefore, the present invention provides an ion trapping treatment apparatus and method using a powdery chelate trapping material capable of efficiently trapping metal ions or ions containing a metalloid element using the powdery chelate trapping material. It is intended to provide.

[0012]

In order to achieve the above object, the present invention provides an ion-trapping apparatus using a powdery chelate trapping material according to the present invention, wherein the ion-trapping apparatus using a powdery chelate trapping material comprises: A reaction means for mixing a chelate trapping material and a solution to be treated to adsorb metal ions or ions containing a metal-like element in the solution to be treated to the powdery chelate trapping material; and a powder from a mixed solution flowing out of the reaction means. A plurality of ion trapping units having solid-liquid separation means for separating the powdery chelate trapping material, and releasing ions containing metal ions or metal-like elements trapped in the powdery chelate trapping material from the powdery chelate trapping material And a regenerating means for regenerating the chelate-trapping material, wherein the plurality of ion-trapping units are arranged in series, and an ion-trapping unit provided at a subsequent stage is provided. Means for introducing the powdery chelate trapping material separated by the solid-liquid separating means into the reaction means of the ion trapping unit provided at the front stage, and the solid-liquid separating means of the ion trapping unit provided at the front stage, particularly at the forefront stage Means for introducing the powdery chelate trapping material separated in the regenerating means, and means for introducing the powdery chelate material regenerated by the regenerating means to the subsequent stage, particularly to the reaction means of the ion capturing unit provided at the last stage. It is characterized by having.

Further, in the above-mentioned device configuration,
In particular, the solid-liquid separation means of the ion capturing unit provided at the last stage is at least one selected from the group consisting of screen filtration, filtration with a packed tower, coarse filtration with a filter, microfiltration, ultrafiltration, and reverse osmosis filtration. Characterized in that it has a filtering means. Furthermore, the powdery chelate trapping material is a combination of a plurality of types of powdery chelate trapping materials according to the type of metal ions or ions containing a metal-class element to be trapped, and the powdery chelate trapping material is natural or It is a trapping material in which a chelate functional group is introduced into regenerated fibers.

The ion-trapping method using the powdery chelate trapping material according to the present invention is characterized in that a solution to be treated containing a relatively high concentration of a metal ion or an ion containing a metal-like element and a powdery chelate trapping material are mixed. A reaction operation of mixing and adsorbing the ions containing the metal ions or the class of metal elements to the powdery chelate trapping material, and a powdery chelate from a mixture of the powdery chelate trapping material mixed in the reaction operation and the solution to be treated. After performing the first ion trapping treatment step of performing a separation operation of separating the trapping material, the solution to be treated and the powdery chelate trapping material having a relatively low concentration of metal ions or ions containing metal-like elements are formed. A reaction operation of mixing and adsorbing the metal ions or ions containing the metal-like element remaining in the solution to be treated to the powdery chelate scavenger, and mixing the reaction operations A separation operation for separating the powdery chelate trapping material from the mixed solution of the powdery chelate trapping material and the solution to be treated is performed at least once in the subsequent ion trapping process step, and the separation operation in the subsequent ion trapping process step is performed. The separated powdery chelate trapping material is mixed with the solution to be treated in the reaction operation in the preceding ion trapping treatment step, and the metal ions captured by the powdery chelate trapping material separated in the separation operation in the first ion trapping treatment step Or, perform a regeneration operation to regenerate the powdery chelate trapping material by releasing ions containing a metal-class element from the powdery chelate trapping material, and perform the powder chelate trapping material after the regeneration operation in the subsequent stage.
Particularly, it is characterized in that it is mixed with the solution to be treated in the reaction operation in the last ion trapping operation.

[0015]

1 to 3 show an embodiment of an ion-trapping apparatus using the powdery chelate-trapping material of the present invention. FIG. 1 shows an embodiment of an ion-trapping unit. FIG. 2 is a schematic system diagram showing an example of an embodiment of an ion capturing apparatus of the present invention using two sets of ion capturing units, and FIG. 3 shows a preferred embodiment of a solid-liquid separation device in the ion capturing unit. It is a schematic system diagram.

First, as shown in FIG. 1, an ion trapping unit 10 used in the ion trapping apparatus of the present invention mixes a powdery chelate trapping material and a solution to be treated, and mixes a desired metal in the solution to be treated. Reaction means 11 for adsorbing ions or ions containing metal-like elements to the powdery chelate scavenger
And a solid-liquid separation means 12 for separating the mixed liquid derived from the reaction means 11 and the powdery chelate trapping material, wherein the solution to be treated flows into the reaction means 11 from the inflow path 13. At the same time, the powdery chelate trapping material flows into the reaction means 11 from the introduction path 14, and the solution to be treated and the powdery chelate trapping material come into mixed contact in the reaction means 11, and the metal ions or the like metals in the solution are mixed. The ions containing the element are adsorbed by the powdery chelate scavenger and removed from the solution.

A mixed solution comprising a powdery chelate trapping material and a solution adsorbing metal ions or ions containing a metal-like element and a solution flows into a solid-liquid separating means 12 from a mixed solution path 15 and is separated into a solid and a liquid. The processing liquid separated by the liquid separating means 12 is
The powdery chelate trapping material that has been led out and separated through the treatment liquid path 16 passes through the lead-out path 17,
Is derived from

As shown in FIG. 2, the ion trapping apparatus shown in this embodiment uses two sets of ion trapping units formed as described above, and connects them to the regenerating means 30 by a specific route. It is. That is, the regenerating means 30 is provided in addition to the first ion capturing unit 10 on the upstream side and the second ion capturing unit 20 on the downstream side,
There is provided a path 41 for introducing the powdery chelate trapping material separated by the solid-liquid separation means 22 of the ion trapping unit 20 from the lead-out path 27 to the reaction means 11 through the introduction path 14 of the reaction means 11 of the first ion trapping unit 10, further,
The lead-out path 17 for leading out the powdery chelate trapping material separated by the solid-liquid separation means 12 of the first ion trapping unit 10 includes:
The outlet 32 of the regenerated powdery chelate trapping material is connected to the inlet 31 of the regenerating means 30 and has a second outlet.
An introduction path 24 for introducing the regenerated powdery chelate trapping material is connected to the reaction means 21 of the ion trapping unit 20.

The solution to be treated flows into the reaction means 11 of the first ion trapping unit 10 from the inflow path 13 and comes into mixed contact with the powdery chelate trapping material introduced from the introduction path 14, and the metal ions or The ions containing the metal-like element are adsorbed by the powdery chelate scavenger and removed from the solution. A mixed solution composed of a powdery chelate trapping material adsorbing metal ions or ions containing a metal-like element and a solution flows into the solid-liquid separation means 12 from the mixed solution path 15 and is subjected to solid-liquid separation. The treatment liquid separated by the solid-liquid separation means 12 is sent to the reaction means 21 of the second ion trapping unit 20 through the treatment liquid path 16, and the separated powdery chelate trapping material is passed through the lead-out path 17 to the regeneration means Sent to 30. The regenerating means 30 can regenerate the powdery chelate trapping material by a similar operation using various commonly used regenerating devices, for example, a batch type regenerating device.

The processing liquid of the first ion trapping unit 10 flowing into the reaction means 21 of the second ion trapping unit 20 from the processing liquid path 16 is mixed with the powdery chelate trapping material introduced from the introduction path 24 by the reaction means 21. Mixing contact is made, and metal ions or ions containing metal-like elements remaining in the treatment liquid are adsorbed by the powdery chelate trapping material and removed from the solution. A mixed solution comprising a powdery chelate trapping material and a solution adsorbing ions containing metal ions or metal-like elements,
The treatment liquid flowing into the solid-liquid separation means 22 from the reaction means 21 is subjected to solid-liquid separation, and the treatment liquid separated by the solid-liquid separation means 22 is led out through a treatment liquid path 26, and the separated powdery chelate trapping material is From the lead-out path 27, it is introduced into the reaction means 11 of the first ion capturing unit 10 through the path 41 and the introduction path 14.

On the other hand, the regenerating means 3 from the solid-liquid separating means 12 of the first ion capturing unit 10 through the lead-out path 17
And the powdery chelate trapping material introduced into the regeneration means 3
0, the regenerating process is performed, and the regenerated powdery chelate trapping material that has released metal ions or ions containing metal-like elements is introduced from the regenerated powdery chelate trapping material outlet 32 into the introduction path 24 of the second ion trapping unit 20. Through the reaction means 21
Will be introduced. Further, waste liquid containing metal ions or ions containing metal-like elements generated by the regeneration treatment is discharged through a waste liquid outlet path 33 of the regeneration unit 30.

As the reaction means 11 and 21, well-known reaction apparatuses, for example, a reaction tank having a stirring means and an online reaction apparatus such as a plug flow type can be used. You can also. In addition, p is added to the reaction means 11 and the inflow path 13 as necessary.
By providing an H control device, the pH of the solution to be treated can be adjusted to a pH suitable for treatment with the powdery chelate trapping material. The reaction time in the reaction means 11 and 21 can be appropriately set according to the characteristics of the powdery chelate trapping material.

As the solid-liquid separation means 12 and 22, various kinds of separation devices can be used as long as they can separate the powdery chelate trapping material and the solution, but the solid-liquid separation in the final stage ion trapping unit is possible. The means 22 is not preferable because only the gravity type sedimentation tank may leak the powdery chelate trapping material. In consideration of the separation efficiency, a filtration means using any of a packed tower of sand, activated carbon, or the like, a mesh filter, or a separation membrane is preferable. In particular, as shown in FIG. Separation membrane 22 serving as filtration means
The solid-liquid separation means 22 in which b is combined is optimal in terms of separation efficiency, separation performance, and the like. The device configuration of the separation membrane is arbitrary, and the optimum configuration can be adopted according to the properties of the solution to be treated and the particle size of the powdery chelate trapping material. Either external filtration or reverse osmosis, or a metal or resin mesh filter may be selected according to the particle size of the powdery chelate trapping material.

When a separation membrane is used as the solid-liquid separation means, it is preferable to provide a gravity sedimentation device before the separation membrane in order to reduce the load on the separation membrane. In particular, when an immersion type separation membrane is used as the separation membrane, it is preferable to use the immersion type separation membrane immersed in a gravity type sedimentation tank.

The route for introducing and discharging the powdery chelate trapping material may be selected according to the properties of the powdery chelate trapping material derived from the solid-liquid separation means and the regenerating means of each unit. In the case of (1), it can be conveyed by a pump, and in the case of solid such as powder, it can be conveyed by a conveyor. Further, depending on the installation position of each means, the powdery chelate trapping material can be derived and introduced by natural fall.

The powdery chelate trapping material is not particularly limited as long as it can absorb metal ions or ions containing metal-like elements in powdery form. ) The most suitable one can be used according to the conditions such as the type of the target metal. For example, those having a molecular structure described in JP-A-2000-169828 are preferable, and those having a chelate functional group introduced into natural or regenerated fibers are preferable. further,
Preferably, the introduced chelating function is iminodiacetic acid or glucamine. The shape of the powdery chelate trapping material is any of powder, short fibers, thread breaks, granules and beads, or a combination thereof.

In the present invention, two or more kinds of powdery chelate scavengers can be used by appropriately mixing. When two or more kinds are mixed, those having an adsorption ability in at least the same pH range are used. When the pH ranges at the time of the regeneration are different from each other, the regeneration may be performed a plurality of times by sequentially adjusting to the respective optimal regeneration pH ranges. This makes it possible to simultaneously remove a plurality of metal ions or ions containing metal-like elements with one device, so that the size of the device and the cost of the device can be reduced.

Then, the ion trapping units are arranged in series in the flow direction of the solution to be treated, like the first ion trapping unit 10 and the second ion trapping unit 20, and the ion trapping unit immediately after regenerating by the regenerating means 30 By introducing a high-performance powdery chelate trapping material into the reaction means 21 of the second ion trapping unit 20 disposed at the subsequent stage, a trace amount of metal ions or similar metal elements remaining in the treatment liquid of the first ion trapping unit 10 Can be effectively removed, and the concentration of metal ions or ions containing metal-like elements in the treatment liquid derived from the ion trapping treatment device can be further reduced.

Further, the second ion trapping unit 2 at the subsequent stage
The powdery chelate capturing material used at 0 only captured a small amount of metal ions or ions containing metal-like elements,
Since there is still room for the ion-capturing ability, by introducing the powdery chelate-trapping material into the first-stage first ion-capturing unit 10, it is possible to recapture ions containing metal ions or metal-like elements in the solution to be treated. Can be used.

As described above, by bringing the solution to be treated into contact with the powdery chelate-trapping material sequentially in the plurality of stages of ion-trapping units, it is possible to effectively remove metal ions or ions containing metal-like elements in the solution. It is possible to take full advantage of the ion-capturing ability of the powdery chelate trapping material by introducing the regenerated powdered chelate trapping material into the subsequent ion trapping unit and sequentially sending it to the preceding ion trapping unit. In addition, the ion trapping can be performed, and the amount of the powdery chelate trapping material used can be reduced.

The first ion capturing unit 10 and the second ion capturing unit 10
Reaction means 11 and 21 in the ion capturing unit 20
Can be arbitrarily set according to the ion concentration in the solution to be processed, the ion concentration remaining in the processing solution of the first ion capturing unit 10, and other conditions. The processing capacity ratio between the former stage and the latter stage may be, for example, in the range of 1: 9 to 9: 1, preferably 3: 9.
7 to 7: 3.

Further, the first ion capturing unit 10 of the preceding stage
The powdery chelate trapping material derived from the above is introduced into the regenerating means 30 to perform a regeneration treatment, and the regenerated powdery chelate trapping material is introduced into the second ion capturing unit 20 at the subsequent stage, and is used while being sequentially sent to the preceding stage. Therefore, it is not necessary to provide a regenerating unit in each ion capturing unit, and only one regenerating unit corresponding to the amount of the powdery chelate capturing material used and the ion concentration in the solution to be treated needs to be provided. In addition, there is no increase in equipment cost and operation cost. In addition, since the powdery chelate trapping material to be regenerated is in a state of capturing a relatively large number of ions, the regeneration means 30
The ion concentration in the waste liquid discharged from the waste liquid outlet path 33 increases, and the regenerating liquid can be saved.

It should be noted that the number of ion capturing units to be installed is arbitrary, and it is possible to arrange three or more units in series. When three or more units are arranged, the powdery chelate trapping material after regeneration is preferably introduced into the last stage ion trapping unit and sequentially sent to the preceding stage, but is introduced into each ion trapping unit excluding the frontmost stage. You may do so. At this time, the powdery chelate trapping material derived from each of the subsequent ion trapping units may be sequentially sent to the preceding step, or a part or all of the powdery chelate trapping material may be introduced to the frontmost step of the ion trapping unit. Further, the powdery chelate trapping material to be sent to the regenerating means may be only from the foremost ion trapping unit, or a part or all of the powdery chelate trapping material derived from the ion trapping unit excluding the last step is sent to the regenerating means. You may do so.

[0034]

EXAMPLE Using the same powdered chelate scavenger, 50
120m of wastewater (solution to be treated) containing ppm boric acid
Processing was performed at 1 / min. The apparatus according to the embodiment has the configuration shown in FIG. 2, in which ion capturing units having a reaction tank (reaction means) having a capacity of 2.5 liters are arranged in two stages in front and rear, and each unit has a powder. The operation was carried out in such a manner that 40 g of each of the chelate traps was present. Further, as a comparative example apparatus, an ion trapping apparatus having a reaction tank having a capacity of 5 liters was used, and the operation was performed such that 80 g of a powdery chelate trapping material was present in the reaction tank. The same means was used in the same manner as the regenerating means, and in the comparative example apparatus, the regenerated powdery chelate trapping material was returned to the reaction tank.

As a result, the concentration of boric acid in the processing solution treated by the apparatus of the example was 1.4 ppm, whereas that of the apparatus of the comparative example was 7.8 ppm.

[0036]

As described above, according to the present invention,
It is possible to effectively remove metal ions or ions containing a metal-like element in a solution to be processed on a scale comparable to that of a single ion capturing apparatus.

[Brief description of the drawings]

FIG. 1 is a schematic system diagram showing an example of an embodiment of an ion capturing unit used in the present invention.

FIG. 2 is a schematic system diagram illustrating an example of an embodiment of an ion capturing apparatus according to the present invention using two sets of ion capturing units.

FIG. 3 is a schematic system diagram showing a preferred embodiment of a solid-liquid separation device in an ion capturing unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... 1st ion capture unit, 20 ... 2nd ion capture unit, 11, 21 ... Reaction means, 12, 22 ... Solid-liquid separation means, 13 ... Inflow path, 14, 24 ... Introduction path, 15
... mixed liquid path, 16, 26 ... processing liquid path, 17, 27 ...
Derivation path, 30 ... reproduction means

Claims (5)

[Claims] 1. An ion-trapping apparatus using a powdery chelate trapping material, wherein the powdery chelate trapping material is mixed with a solution to be treated, and a metal ion or an ion containing a metal-like element in the solution to be treated is mixed. A plurality of ion capturing units having a reaction means for causing the powdery chelate capture material to be adsorbed to the powdery chelate capture material, and a solid-liquid separation means for separating the powdery chelate capture material from the mixed solution flowing out of the reaction means; Regenerating means for regenerating the powdery chelate trapping material by releasing the trapped metal ions or ions containing the metal-like element from the powdery chelate trapping material, and arranging the plurality of ion trapping units in series, The powdery chelate trapping material separated by the solid-liquid separation means of the ion trapping unit provided at the reaction means of the ion trapping unit provided at the previous stage Means for introducing, means for introducing the powdery chelate trapping material separated by the solid-liquid separation means of the ion trapping unit provided in the preceding stage into the regenerating means, and powdery chelating material regenerated by the regenerating means provided in the latter stage An ion capturing unit using a powdery chelate capturing material. 2. The solid-liquid separation means of the ion capturing unit provided at the subsequent stage is selected from the group consisting of screen filtration, filtration by a packed tower, coarse filtration by a filter, microfiltration, ultrafiltration and reverse osmosis filtration. The ion trapping treatment apparatus using a powdery chelate trapping material according to claim 1, further comprising at least one kind of filtration means. 3. The powdery chelate trapping material according to claim 1, wherein the powdery chelate trapping material is obtained by combining a plurality of kinds of powdery chelate trapping materials in accordance with the kind of a metal ion or an ion containing a metal-like element to be trapped. 2. An ion capturing apparatus using the powdery chelate capturing material according to 2. 4. The powdery chelate trapping material according to claim 1, wherein the powdery chelate trapping material is a trapping material in which a chelate functional group is introduced into natural or regenerated fibers. Ion trapping treatment device using 5. A treatment solution containing a relatively high concentration of a metal ion or an ion containing a metal-like element and a powdery chelate scavenger are mixed to convert the metal ion or the ion containing a metal-like element into the powdery form. A first ion trapping process step of performing a reaction operation of adsorbing to the chelate trapping material and a separation operation of separating the powdery chelate trapping material from a mixed solution of the powdery chelate trapping material and the solution to be treated mixed in the reaction operation After performing, the metal ions or ions containing metal-like elements are mixed in a relatively low concentration of the solution to be treated and the powdery chelate trapping material and the metal ions or the metal ions remaining in the solution to be treated A reaction operation for adsorbing ions containing a metal-like element to the powdery chelate trapping material; and a powdery chelate trapping process from a mixed solution of the powdery chelate trapping material mixed with the reaction operation and the solution to be treated. And a separation operation for separating the trapping material is performed at least once in the subsequent ion trapping treatment step, and the powdery chelate trapping material separated by the separation operation in the subsequent ion trapping treatment step is subjected to a reaction operation in the preceding ion trapping treatment step. Mixed with the solution to be treated in the first ion trapping treatment step, the ions containing metal ions or metal-like elements captured by the powdery chelate trapping material separated by the separation operation in the first ion trapping treatment step are released from the powdery chelate trapping material. Performing a regeneration operation for regenerating the powdery chelate trapping material, and mixing the powdery chelate trapping material after the regenerating operation with a solution to be treated in a reaction operation in a subsequent ion trapping treatment operation; Trapping method using a material.