JP2011201731A - Mesoporous powder, metal ion sensor, method for detecting metal ion, metal ion adsorbing material and method for recovering metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide mesoporous powder which can be bonded to an organic functional material with the force stronger than that of mesoporous powder comprising sole silica and to provide a metal ion sensor obtained by using the mesoporous powder, a method for detecting a metal ion, a metal ion adsorbing material and a method for recovering a metal.SOLUTION: The metal ion sensor uses the mesoporous powder comprising silica and a metal oxide. and is obtained by holding a probe, which adsorbs the metal ion contained in a liquid and colors, in the mesoporous powder. The method for detecting the metal ion comprises the steps of: charging a predetermined amount of the metal ion sensors into the liquid to be detected and the pH of which is adjusted to be suitable for the metal ion to be detected and the kind of the probe; and detecting whether there is a metal ion-peculiar color and the concentration of the metal ion. The metal ion adsorbing material is obtained by fixing the probe having a metal ion adsorbing group onto the surface of the mesoporous powder. The method for recovering the metal is for recovering the metal from the metal ion-containing liquid, in the concrete, and comprises the steps of: charging the metal ion adsorbing material into the liquid to be treated the pH of which is adjusted to be suitable for adsorbing the metal ion to be recovered to adsorb the desired metal ion in the liquid to be treated on the metal ion adsorbing material; separating the metal ion-adsorbed adsorbing material from the liquid to be treated; moving the metal ion from the separated adsorbing material to a recovery liquid; separating the metal ion-separated adsorbing material from the recovery liquid; and vaporizing the recovery liquid to recover the metal.

Description

The present invention relates to a mesoporous powder that is porous with a regular arrangement, a metal ion sensor that holds a probe that adsorbs and colors a metal ion contained in the liquid, and the metal The present invention relates to a metal ion detection method using an ion sensor, a metal ion adsorbent in which a probe that adsorbs metal ions in a liquid is fixed to the mesoporous powder, and a metal recovery method using the adsorbent.

Among the mesoporous powders, silica powder is used as a support for various organic functional materials, but those having higher strength and bonding strength have been demanded.
Further, by using silica as a support for a probe having the ability to color by contact with metal ions in mesoporous powder, it has been used as a metal ion sensor.
This also increases the strength and bonding force as a carrier, and further stable utilization has been desired.
In addition, it has recently been proposed by the present inventors that such a sensor can be used as an adsorbent for extracting metal from a metal ion-containing liquid such as a waste liquid by utilizing coloration by adsorbing metal ions. It was.

  In view of such circumstances, the present invention provides a mesoporous powder that can be combined with an organic functional material more strongly than a mesoporous powder of silica alone, a metal ion sensor, a metal ion detection method, a metal ion adsorbent, and a metal recovery method using the mesoporous powder. The purpose is to provide.

The mesoporous powder of the invention 1 comprises silica and a metal oxide.

The metal ion sensor of the invention 2 is a metal ion sensor in which a probe that adsorbs and colors a metal ion contained in a liquid is held in a mesoporous powder, and the mesoporous powder is the mesoporous powder of the invention 1. It is characterized by that.

The metal ion detection method of the invention 3 is a metal ion detection method for detecting the type and concentration of the metal ion contained in the liquid, the metal ion sensor of the invention 2 for detecting the metal ion and its probe. A predetermined amount is put into a liquid to be detected adjusted to a pH suitable for the kind of the above, and the presence and concentration of a color specific to metal ions is detected.
Invention 4 is characterized in that in the metal ion detection method of Invention 3, the metal ion sensor used for concentration detection is separated and recovered from the liquid to be detected, and the metal ions adsorbed on the sensor are removed and regenerated.

The metal ion adsorbent of the invention 5 is a metal ion adsorbent used for adsorbing the metal ions contained in the liquid to be treated and separating and recovering the metal ions from the liquid to be treated. A probe having a metal ion adsorption group is fixed on the surface of the mesoporous powder.

The metal recovery method of the invention 6 is a metal recovery method for recovering a metal from a liquid containing metal ions, and the metal according to the invention 5 is contained in a liquid to be treated adjusted to a pH suitable for adsorption of the metal ions to be removed. An ion adsorbent is introduced, desired metal ions in the liquid to be treated are adsorbed on the metal ion adsorbent, the adsorbent is separated from the liquid to be treated, and metal ions are separated from the separated adsorbent into the recovered liquid. The metal is recovered by separating the adsorbent from which the metal ions have been separated from the recovered liquid and evaporating the recovered liquid.
Invention 7 is characterized in that in the metal recovery method of Invention 6, the adsorbent separated from the recovered liquid is reused.

Since the mesoporous powder of the invention 1 is composed of silica containing a metal, the strength of the mesoporous powder can be increased not only by silica but also by the bond between the metal and silica, and the bond with the organic functional material has been improved. Silica had an anxious bond called the physical bond between silica and oxygen, but it has a stable strength relationship due to the chemical bond between the metal, silica and oxygen, so it forms not only the outer surface but also the porous structure. Even on the inner surface of the hole, it could be strongly bonded to the organic functional material.

In the metal ion sensors of the inventions 2, 3, and 4 that make use of the properties of the mesoporous powder of the present invention and the detection method using the same, the pH adjustment of the liquid to be detected that is performed for the adsorption of metal ions is performed. However, since the probe does not fall off or the mesostructure does not collapse, it can be used repeatedly by removing the adsorbed metal ions.
Moreover, since the metal ions to be adsorbed can be changed by adjusting the pH of the liquid to be detected, various metal ions can be detected.

Further, as shown in Inventions 5, 6, and 7, when the adsorbent using the mesoporous powder of Invention 1 is used as a means for recovering metal from the liquid to be treated, the recovered adsorbent can be used repeatedly. And the same adsorbent can be used to recover different metal ions.

19 (20-01-01), 9 (20-02-01), 4 (20-03-01), 2.3 (20-04-01), 1.5 (20 at different Si / Al ratios -05-01), and 1.0 (20-06-01), Cubic Im3aluminosilicate nanocomposites. By XRD (X-ray analysis). Wide-Angle XRD patterns of metal / silica nanocomposites with differential space groups of P6mm (01), Pm3n (02), Fm3m (03), Fd3m (04), 053, M ratios of 2.33 (04), respectably. Different Si / Al ratios 19 (20-01-01), 9 (20-02-01), 4 (20-03-01), 2.3 (20-04--01), 1.5 (20-05 -01), and 1.0 (20-06-01), N2 isothermal patterns of 3-dimensional cubic Im3aluminosilicate nanocomposites HRTEM image and FTD (inserts) pattern TEM, FTD image of Cubic Im3m Al / silica nanocomposite sensors manufactured by addition of Al / Si ratio 9, H2DSPy (21-02), TMPyP (22-02) probe [111] (A) and [110] (B) Recorded on the zone axis. XRD pattern pattern of Cubic Im3m Al / silica nanocomposite sensors manufactured by addition of Al / Si ratio 9, H2DSPy (21-02), TMPyP (22-02), DZC (23-02) probes N2 isotherm pattern of Cubic Im3m Al / silica nanocomposite sensor manufactured with addition of Al / Si ratio 9, H2DSPy (21-01), TMPyP (22-01), DZC (23-01) probes Multi-metal detection signal reaction as a pH function using H2DSPy, TMPyP and DZC-immobilized aluminosica (Al / HOM-1) monoliths (20-02-01) Color change of M / HOM / DZC sensor Cu (II) in a visible sensing environment (eg, pH of 5, R _t > 90 sec. Sensoramount of 4 mg, volume of 10 ml, temperature 25 ^° C) [26-02] [22-02] during ion analysis recognition -02] Concentration-dependent change illustration of UV / Vis reflectance spectroscopic reaction of sensor Hg (II) [28-02] during ion analysis recognition in a visible sensing environment (eg, pH of 11, R _t > 120 sec, sensoramount of 4 mg, volume of 10 ml, temperature 25 ^° C) -02] Concentration-dependent change illustration of UV / Vis reflectance spectroscopic reaction at sensor Illustration of concentration-dependent changes in UV / Vis reflectance spectroscopic responses of [23-02] sensor during the recognition of Hg (II) analyte ions [33-02] at optimal sensing conditions (such as pH of 11, R t> 20 sec., sensoramount of 4 mg, volume of 10 ml and temperature of 25 ^o C) Calibration curve (A-Ao & [Cu (II)] concentration, where Ao and Acid the balance of TMPyP-probe and [Cu-TMPyP] ^{n +} complex at λ = 552 nm) of optical 02 recognition of Cu (II) ion (in the absolute of interference, see the black curve) and in the addition of interfered rations (see the red curves). The inlet in the graphs the amplification for the low-limit colorimetric response for Cu (II) ions (experimental data). The graph was represented by a linear fit line in the linear contention range before saturation. Error bars represent standard tolerances of 1-5% of 10 replicate analysis data. [See Table 26-02] It is process drawing which shows the metal collection | recovery system of Example 3.

The present invention relates to a mesoporous powder and succeeds in improving strength and adhesion to a probe, which are weak points of silica mesoporous powder.
Specifically, as shown in Example 1, a mesoporous powder in which a metal oxide and silica were mixed was realized.
If only silica is used, only the desired stable mesoporous layer can be obtained in the amorphous due to the physical properties of silica. However, by adding metal, the whole has a regular and stable structure.
In addition to the metal elements and oxides thereof shown in the following examples, transition metal elements, metalloids, oxides in typical metal regions, and the like can be required.
It is desirable that the metal element is 0.05 to 4, preferably 0.1 to 4, with respect to the silicon element 1 in terms of mass ratio.
In the mixing of metal and silica, when one is less than 1/3 of the other, the properties of the smaller element in the mixture are markedly reduced.
In view of this, the present invention requires a monolith that maintains both the properties of the metal and silica, so it is considered appropriate to maintain the relative ratio as described above.
Specifically, when metal elements are diluted to less than one-third (refer to the law of one-third), functional points (ordered pore structure, surface area, and pore volume are degraded. But the framework is preserved). In the opposite case, the properties of silica are lost and the framework is lowered.

In the production of the metal-containing mesoporous silica of the present invention, the surfactant used in the production is Brij-type (C _x EO _y ) “for example, Brji 56, Brji 76, Brji 97, CnTMA-B or-C, P123 F108”. Most effective.
By using the surfactant, a mesoporous structure such as a hexagonal cubic hole is formed at the nanoscale level, and helps to form a large area of the M / HOM structure.

Alkanes are used to create a regular organization structure by making the basic structure as a template and attaching target atoms around it.
Even if it is a raw material from which a regular organization structure is difficult to obtain, it can be made into a monolist of a regular organization structure by using the method.
Such metal-containing mesoporous silica is not only easy to bond with organic probes having a factor that adsorbs metal ions in the liquid, but once bonded, the bond is due to the electronic structure. It is not easily separated even by fluctuations in pH or the like in the liquid.
This function is a factor that facilitates repeated use when used as a sensor or an adsorbent for metal ion recovery shown in Examples 2 and 3 below.

In particular, when using a probe with different metal ions adsorbed due to the difference in pH in the liquid and using it as a sensor to visually inspect the metal ion concentration by its coloration function, the contained metal ions are unknown However, it can be used repeatedly by changing the pH.
Furthermore, when recovering metal ions in the liquid as shown in Example 3, when used as a metal ion adsorbent, the use of the adsorbent can be reduced, and the possibility of secondary pollution occurring can be reduced. Further, since the constituent material of the adsorbent does not elute into the recovery liquid, it is possible to recover extremely high purity metal in which a predetermined metal ion exists in the recovery liquid.

The sensor and the adsorbent use a support having a mesoporous structure.
The mesoporous structure is a kind of porous structure and means a large number of pores (mesopores) having a uniform and highly ordered size and shape.
It is a group of porous materials that are known to have various properties depending on the type of network (spatial symmetry) created by the pores, the manufacturing method, and the like. Further, such a structure is likely to occur in pores having a diameter of 2 to 50 nm called a mesopore region, but in the present invention, micropores (pores less than 2 nm) smaller than mesopores. Or a mesoporous structure as a concept including a structure having macropores (pores larger than 50 nm) larger than mesopores.
Highly ordered means a state in which cubic or hexagonal mesoporous structures are regularly arranged on the surface or inner wall surface in three dimensions, for example, cubic Ia3d, Pm3n, Im3m, or hexagonal P6m structure. When these structures are present in a wide range, a large amount of a compound as a probe can be supported, and the entire metal ion adsorption amount can be increased.
In particular, in the case of a hole diameter large enough to allow the inflow of the target liquid, fixing the probe also to the inner surface of the hole dramatically increases the contact and reaction area with the target liquid, and the coloration and adsorption thereof. The amount can be increased dramatically.
A porous carrier having such a structure is referred to as M / HOM (High Ordered Mesoporous), but in the present invention, since silica contains a metal, it is referred to as M / HOM.
The form of M / HOM includes a thin film form and a monolith form. The monolith form usually refers to various forms other than a thin film, such as fine particles, particles, block-like forms and the like. Moreover, although the BET specific surface area of M / HOM is so good that it is large, it is 500 m < ² > / g or more normally, Preferably it is 800 m < ² > / g or more.

The sensor and the adsorbent for recovering metal ions of the present invention are those in which a compound having a metal ion binding group (hereinafter referred to as Probe) is chemically bonded to the inner surface of the M / HOM pores.
By doing so, due to the uniformity of the pores of M / HOM, not only the liquid penetrates into any pore, but also the distance between the central part of the penetrated liquid and the bonding group is constant, In any pore, metal ions in the liquid can be adsorbed with a similar probability.
Furthermore, when the diameter is at the nano level, all of the metal ions in the liquid can also be expected to come into contact with the bonding group, and as a result, it can also adsorb low concentrations of contained metal ions, which was impossible in the past. Is something that can be done.

In addition, since the M / HOM and the Probe are combined and integrated as described above, even if a physical force is applied, the compound is not easily detached from the M / HOM and affects the binding. Only the metal ions can be recovered by releasing the adsorbed metal ions by the chemical treatment that is not performed.
That is, metal ions can be recovered without mixing adsorbent components.
Moreover, since the adsorbent from which the metal ions have been released in this manner means that the adsorbent is returned to the state before use, there is no problem in adsorbing the metal ions by using this again.

As the probe, any probe can be used as long as it has a binding group capable of adsorbing a metal ion to be collected and can bind to the inner surface of the M / HOM as described above.
For example, the chelate compound which selectively couple | bonds with various metals is mentioned. Specifically, ethylenediaminetetraacetic acid (EDTA: C10H16N2O8) selectively adsorbs Ca ²⁺ , Cu ²⁺ , Fe ^{3+, and the} like. Dithizone (Cu, Zn, Ag, Hg, Pb), cuperone (Ti, Fe, Cu), quinaldic acid (Cu, Zn, Cd), α-nitroso-β-naphthol (Co, Pd), dimethylglyoxime (Ni , Pd). Further, as a monomer or oligomer of a chelate resin, which is a polymer of a chelate compound, for example, carboxylic acid type resin (Cu, Ni, Zn), polyamine type resin (Hg, Cd, Cu), polyimine type (Hg) resin, thiol Monomers or oligomers such as mold resins (Ag, Hg, Au), β-diketone resins (U), hydroxyl resins (Mo, V), azo resins (Cu, La, Zr, Pd) can be used. Chitosan {(C ₆ H ₁₁ NO ₄ ) n} also has metal ion adsorption selectivity (Fe, In, Ni, Cd, Zn). (The metal in the parenthesis indicates a metal that can be selectively adsorbed.) By adjusting the pH value, temperature, concentration, etc. of the liquid in which various metal ions are present, a specific metal can be selectively adsorbed on the probe. In addition, since the chelate compound can selectively adsorb a very small amount of metal (for example, ppb order), the structure of the present invention makes it possible to exert it and the target metal ion contained in the liquid. The target metal ions are efficiently and selectively adsorbed even with a small amount of.

Various methods can be cited as a method for binding (modifying) such a probe to M / HOM (also referred to as a composite method). For example, when the probe to be held in the M / HOM is neutral, the reagent impregnation method (REACTIVE & FUNCTION POLYMERS, 49, 189 (2001), etc.) is anionic, and the cation In the case of an exchange method or cationicity, an anion exchange method is used.
These compounding methods belong to known general technical fields, not special conditions and operations. Therefore, details of these general technical fields can be easily implemented by referring to reviews, literatures, and the like regarding the solid adsorption field.

Specifically, the following method can be easily implemented.
1) M / HOM silica is surface treated with a cationic organic reagent (eg, cationic silylating agent) to impart a cationic functional group to the M / HOM silica, and then the cationic A method in which M / HOM silica is contacted with an aqueous solution or an alcohol solution of an anionic probe to adsorb the probe into the M / HOM silica.
2) A method in which Probe is adsorbed and supported in M / HOM silica by contacting M / HOM silica with an organic solvent solution of Probe and removing only the organic solvent.
3) Surface treatment of M / HOM silica with a silylating agent having a thiol group, followed by oxidation treatment of the thiol group on the surface to give an anionic functional group to the M / HOM silica The method in which the anionic M / HOM silica and an aqueous solution of a cationic probe are brought into contact with each other to adsorb the probe into the M / HOM silica.
4) A method in which the probe is filled in the pores and on the surface and then treated with an organic solvent solution of a cationic organic reagent to fix the probe in the pores and on the surface.
5) A probe and a cationic organic reagent are mixed in advance, the organic solvent solution of the obtained reagent complex is brought into contact with the silica, and only the organic solvent is removed by filtration or distillation to remove the probe in the silica. Method to carry on.
In addition, in order to support the above-mentioned NN on M / HOM as a probe, NN is dissolved in ethanol, this solution is brought into contact with M / HOM, and M / HOM is impregnated with NN. In this way, an M / HOM in which NN is regularly and densely supported is completed.

Further, as the M / HOM has a larger porous (pore) density with a higher order of crystal structure and a larger BET specific surface area, more probes are regularly supported on the surface of the M / HOM and the inner walls of the pores. For example, preferably, Probe can be adsorbed to M / HOM in which structures such as cubic structures Pm3n, Fm3m, Ia3d, and hexagonal structure P6m are formed in a wide range.
This is because the chemical properties of the M / HOM inner surface of the pores are regular, and when the probe is chemically bonded in a state meeting the properties, the probe is also ordered in accordance with the regularity of the inner surface of the pores. By being ordered.
These can be bonded to M / HOM silica shown in the following examples via OH groups.

With Probe alone, it is difficult to separate the metal ion binding group and the metal ion inside the liquid by preventing the contact between the metal ion binding group and the metal ion, even if the metal ion is adsorbed inside the aggregate. For this reason, it is not possible to recover so much metal ions as compared to the amount of Probe used. Also, separation of the metal ions once adsorbed is completely difficult as long as agglomeration occurs, and as a result, the recovery efficiency is deteriorated.

In contrast, in the present invention, one molecule of Probe can be used for metal ion adsorption.
In the structure of the present invention, since the arrangement is regular (5 nm to 25 nm), “steric hindrance” (structural loss) does not occur.
Since the metal ion-containing liquid easily penetrates into the pores of the mesoporous structure, it easily comes into contact with Probe (reactive group) supported on M / HOM quickly. Conversely, when the adsorbed metal is liberated, it quickly comes into contact with the liberated component, and metal ions are liberated too much.

For example, in the case of a chelate resin alone, on the surface of the chelate resin, all surface atoms do not have a chelate (adsorptive group) effectively, and there are atomically discrete chelate reaction ends. It has become. Even when a metal ion is adsorbed only by the chelating resin, it cannot be controlled which part of the chelating resin is attached. Also, metal ions are expected to be adsorbed (also referred to as extraction) to the chelate functional group in contact with the metal ion-containing liquid, but almost all metal ions are adsorbed inside the chelate resin that is difficult for the metal ion-containing liquid to penetrate. It is thought that it is not done. That is, the metal ion adsorption efficiency is very poor.
Further, when releasing metal ions adsorbed on the chelate resin (also referred to as back extraction), it becomes difficult to take out the metal ions adsorbed inside the chelate resin. Even when this chelate resin is used repeatedly, the efficiency of adsorption and separation / recovery (extraction / back-extraction) of metal ions becomes worse due to the effects of residuals in the chelate resin. It will deteriorate significantly.

Even in the case of using such a chelating resin (monomer or oligomer), the adsorbent (Material of metals metal ion) of the present invention has an atomic arrangement aligned with the large specific surface area of M / HOM even when such a chelate resin (monomer or oligomer) is used. Can be used to form chelate functional groups with a large actual reaction area on the surface of the M / HOM.
In other words, in M / HOM, the reaction ends of the chelate have almost the same properties. Moreover, it has a chelate reaction end in a large amount on the M / HOM surface and the inner wall of the pores, which cannot be realized by a conventional chelate resin alone.
Since the chelate functional group selectively adsorbs metal ions or chelated ions, the adsorption efficiency of metal ions becomes very good. Further, the adsorbed metal ions can be extracted by back extraction. Furthermore, when the chelate resin is used alone, the physical and / or chemical strength of the resin itself is insufficient, so deterioration due to repeated use of the chelate resin is large, but the chelate resin is supported on M / HOM. Since the physical and / or chemical strength of M / HOM as a skeleton is sufficient, deterioration due to repeated use is small.
Examples of the present invention are illustrated below.

In this example, examples of metal-containing mesoporous silica powder are shown in Tables 1 to 19.
The method is as follows.
Surfactant, silica source and metal source, and if necessary, alkane (Alkane) in the amount shown in the following table, hydrochloric acid aqueous solution (dissolved in the solution and kept for several minutes in the hot water bath at the reaction temperature indicated by T The solution was dissolved to obtain a transparent solution, that is, a homogeneous solution, and an M / HOM can be prepared in a short time of 5 to 10 minutes.
By adding alkanes such as dodecane, the pore size of the mesoporous structure can be controlled.
About 2 g of aqueous HCl (H 2 O / HCl ”pH = 1.3) was quickly added to the sol-gel solution. Addition of an acidic aqueous HCl solution to the composition domain of a homogeneous solution results in rapid exothermic hydrolysis and condensation of TMOS. Thereafter, when the flask is evacuated and baked at 450 ° C. to 500 ° C. (usually 470 ° C.), the alcohol is quickly removed and a translucent M / HOM monolith is produced.
As described above, M / HOM having a silicon / metal ratio (Si / M) shown in each table was synthesized.
The structures of the obtained M / HOM monoliths were as shown in Tables 1 to 20.

This example shows a specific example of creation of a sensor using Al / HOM particles and use of the obtained sensor shown in Table 20 of Example 1.
Each M / HOM particle shown in Tables 1 to 19 shown in Example 1 can be used as a sensor in the same manner as in this example, and the performance thereof is also the same.
Tables 21, 22, and 23 show examples in which different probes of Al / HOM are combined.
Support of metal ion adsorption compound (Probe) on M / HOM.
M / HOM is a metal silica particle having highly ordered pores, and various compounds can be supported on the surface of the M / HOM and the inner walls of the inner pores. In this embodiment, a probe capable of selectively adsorbing target metal ions is supported. For example, in the case where Probe is supported on a cage-like or cylinder-like cubic monolith, it is performed as follows.
Probe is dissolved in absolute ethanol (0.01 M / l) and 3.5 g M / HOM is immersed and held at room temperature for 10 minutes. Next, it is heated to 60 ° C. to impregnate the probe with M / HOM and saturated in 24 hours. If the solid is washed with water and dried at 60 ° C. for 45 minutes to remove ethanol, a sensor carrying Probe can be obtained. By this operation, the contained metal and Probe are electronically bonded to the M / HOM surface and the pore (pore) surface of the inner wall surface of the Probe molecule.

As a result of using the sensor manufactured as described above as shown in the table below, the result shown in the figure was obtained.

[0.5 ppm] Visible sensor analysis during discrimination of Pd (II), Bi (III), Pb (II), Zn (II), Hg (II) and Cd (II) ions [(35-01), (35-02), (35-03), (35-04), (35-05), and (35-06)] using the tolerance matrix species tolerance limit
Note: Sensor (23-02) under normal sensing environment (R _t , pH value 2.0, 5.0, 7.0, 9.5, 11.0, and 12.5, temperature setting 25 ^° C) ) Selectivity obtained from each target metal within the addition of interfering external ions, electron species and composite agents using (Al / HOM / DZC) (see Tables 29-34).

In this example, the sensor particles shown in Example 2 were used as a metal ion adsorbent in the liquid.
[Making metal ion-containing liquid from urban ore]
Separation and recovery of metal ions can be effectively used for recovery of metals, especially rare metals, from urban ores.
A method for producing a liquid from which metal ions contained in city ore are eluted may be as follows.
1) When materials containing rare metal ions such as Co, In, and Nb obtained from mobile phones and personal computers are immersed in an aqueous nitric acid solution, a large number of metal ions such as Fe, Cu, and Co (also in urban ores) Ingredients) are dissolved, and the components not dissolved in the acid remain as solids. If they are removed by filtration, a metal ion-containing liquid is obtained.
Of course, the present invention is not limited to the metal ion-containing liquid obtained in this way, but also waste liquid that is generally considered to have a high concentration of metal ions, such as the waste liquid discharged in processes such as plating and metallurgy. Also in the purification, it is possible to recover the contained metal along with the purification of the waste liquid.

Based on the process chart shown in FIG. X, the recovery method of the present invention will be described below in the order of each process.
In the first step, a pH adjusting agent is injected so that the pH determined based on the adsorbent used and the metal ions to be recovered is used by the metal ion-containing liquid.
A metal ion adsorbent is added to this liquid, and is maintained at a temperature suitable for adsorption, and agitated and mixed. Among the contained metal ions, the type of metal determined by the pH and the adsorbent. Only ions are adsorbed on the adsorbent.
Any pH adjuster may be used as long as it can adjust the pH of the solution without inhibiting the bond between Probe and M / HOM and the bond between the metal ion to be recovered and Probe as shown in the Examples.
Since the adsorbent adsorbing the metal ions in the second step and the first step is precipitated in the liquid, the adsorbent and the liquid are separated using a filtration device or the like.
Since the metal ions are bound to the adsorbent separated in the third step and the second step, the adsorbent is adsorbed by the adsorbent by introducing it into the recovery liquid containing the component (separation component) for separating them. The metal ions are separated and released into the recovered liquid.
As the separation component of the recovered solution, any component can be used as long as it can separate metal ions from Probe without inhibiting the binding between Probe and M / HOM, as shown in the Examples.
Fourth step Then, the adsorbent (metal ions are separated) from the recovered liquid is separated by a filter or the like.
Fifth Step When the liquid component is removed by heating or vacuum evaporation of the recovered liquid excluding the adsorbent in the fourth step, the metal component remains.
The metal component thus obtained can be melted to produce an ingot or the like, which can be reused.
Even in a liquid containing a plurality of metal ions, one kind of metal ion can be recovered with high purity by the above-described manner.

[Recovery of metal ions from a liquid containing multiple metal ions]
In the above-mentioned method, it is possible to recover with high accuracy that the adsorption and separation are sequentially performed from metal ions having a high concentration.
Then, as shown in FIG. 1, the metal ion-containing liquid from which the adsorbent has been separated in the second step is used again as the metal ion-containing liquid in the first step so as to be compatible with the remaining high-concentration metal ions. In addition, by adjusting the adsorbent and pH and repeating the above steps, a plurality of metal ions can be selected and recovered with high purity.
[Metal recovery]
In order to recover the metal with high purity, it is natural that the recovered liquid does not contain other metal ions in advance.
When the recovered liquid is heated to evaporate the water, the metal is recovered, but in this case, the adsorbent component is not included at all, and most of the chemical component that separates the metal ions is evaporated. As a result, an extremely high purity metal could be obtained.
In short, any material that satisfies the above conditions can be used depending on the materials of Probe and M / HOM. By doing so, the adsorbent returns to the state before the metal ion adsorption, and can be reused.
However, if not reused, it is possible to burn the adsorbent and recover the metal, but components (such as Si) that constitute the adsorbent are not mixed as impurity components.
Examples of the present invention will be described below.

[Reuse of adsorbent]
As shown in FIG. 1, the adsorbent separated in the fourth step disappears due to separation of metal ions, and returns to the state before use. Therefore, it is not difficult to designate and use this as an adsorbent to be introduced into the liquid in the first step.
This is apparent from data obtained by repeated use in the following examples.

[Explanation of measurement methods]
Various symbols used in the following examples will be described.
This is used in each table or drawing unless otherwise specified.
In each example, the characteristics and other numerical values are numerical values obtained as follows.
“Q” is the saturated adsorption capacity of the probe (mmol / g)
The saturated adsorption force at the time of saturation of the probe can be obtained by the following calculation formula. Q _t = (C _o −C _t ) V / m, Q _t is the adsorption amount at the time of saturation t, V is the amount of solution (L), m is the mass (mass) of M / HOM carrier (g), C _o and _Ct is initial concentration and saturated concentration “Rt” is probe response time (sec)
Rt is a numerical value obtained by observing that the color of the probe and the ultraviolet light / visible light absorption spectrum continuously change due to the adsorption of metal ions, and is called a response time.
In the examples, UV-Vis spectrometer detection values were used.
“D _L ” detection limit (mol dm ⁻³ )
The detection limit value of the metal ion of the probe shows the calibration measurement result of the spectral absorption (A-Ao) of the probe measured at λ _max of 534 nm with divalent Co at different concentrations, X axis = 2 It is a value calculated from the linear part shown in the graph with the value Co, Y axis = A, Ao).
Specifically, this is based on the calculation formula of D _L = k ₁ S _b / m. When k ₁ = 3 at the time of detection value determination, S _b is the standard deviation of the blank, and m is the calibration graph in the linear region. The slope of
“L _Q ” Quantification Limit Factor (mol dm ⁻³ )
The detection limit value of the metal ion of the probe shows the calibration measurement result of the spectral absorption (A-Ao) of the probe measured at λ _max of 534 nm with divalent Co at different concentrations (X axis = It is a value calculated from the linear portion shown in the graph with a bivalent Co, Y axis = A, Ao).
Specifically, it is based on the calculation formula of L _Q D _L = k ₂ S _b / m. When k ₂ = 10 when the detection value is determined, S _b is the standard deviation of the blank, and m is the linear range. Indicates the slope of the calibration graph.
“D” ion diffusion coefficient (cm ² .min ⁻¹ )
The ion diffusion coefficient (cm ² .min ⁻¹ ) indicating the migration rate of metal ions to the nano-sized porous material is calculated using the following equation.
D = 0.03 r ² / t _1/2
r is half the diameter (Dp) of the nanoadsorbent,
t _1/2 is _half of the reaction signal time Rt “Log Ks” metal ion ligand stability constant The composite [metal-receptor] ^{n +} stability constant (log K _s ) at a specific pH value is given by Calculation is possible.
log K _s = [ML] _S / [L] _S × [M]
In the formula, [ML] is the total number of metal ion binders (ligant).
[M] is the concentration of the chelate that is not bound to the metal ion, and [L] is the concentration of the chelate that is not bound to the metal of the metal ion binder (ligant) of the probe.
S refers to the total concentration of the metal complex and ligand.
Detection range of maximum and minimum concentrations determined from “D _R ” ultraviolet spectrum (mol dm ⁻³ )
“No *” repetition count Indicates the number of times the adsorbent is used, where 1 is the first use and 2 or more is the reuse.
"Efficiency (E)" Efficiency of adsorbent design (%)
The reuse of the adsorbent is due to the successful removal of the metal ions once adsorbed without causing a significant change in the structure and properties of the adsorbent.
In order to express this as a numerical value, No * indicates how the response time (R _tn ) of the n-th adsorbent changed as compared to the initial response time (R _t1 ) as efficiency (E). It was. The calculation formula is as follows.
E = R _tn / R _t1 (%)
“(S)” Molar ratio of metal ion to adsorbent S = number of moles of metal ion / [M−receptor] number of moles of ^{n +} S _BET is the BET specific surface area Dp determined by the BET specific surface area nitrogen adsorption method. (Pore) size (nm)
The central pore diameter Vp calculated by the BJH method is the pore volume (cm ³ / g)
Volume “a *” obtained from S _BET , Dp and pore shape
Pm3n, Ia3d and Im3m cubic unit cell coefficients (nm) are calculated as follows.
_{(A Pm3n = d 210 √5,} a Ia3d = d 211 √6, and a Im3m = d 110 √2), d is the spatial distance (distance spacing) between hkl diffraction index.

Claims (7)

A mesoporous powder that has a regular arrangement and is porous, and is composed of silica and a metal oxide. A metal ion sensor in which a probe that adsorbs and colors a metal ion contained in a liquid is held in a mesoporous powder, wherein the mesoporous powder is the mesoporous powder according to claim 1. Metal ion sensor. A metal ion detection method for detecting the type and concentration of metal ions contained in a liquid, wherein the metal ion sensor according to claim 2 is adjusted to a pH suitable for the types of metal ions to be detected and their probes. A metal ion detection method, wherein a predetermined amount is introduced into the liquid to be detected, and the presence and concentration of a color specific to metal ions is detected. The metal ion detection method according to claim 3, wherein the metal ion sensor used for concentration detection is separated and recovered from the liquid to be detected, and the metal ions adsorbed on the sensor are removed and regenerated. Detection method. A metal ion adsorbent used for adsorbing metal ions contained in a liquid to be treated and separating and recovering metal ions from the liquid to be treated, wherein the mesoporous powder surface according to claim 1, A metal ion adsorbent characterized by fixing a probe having a metal ion adsorbing group. A metal recovery method for recovering a metal from a liquid containing metal ions, wherein the metal ion adsorbent according to claim 5 is introduced into a liquid to be treated adjusted to a pH suitable for adsorption of metal ions to be removed, Desired metal ions in the liquid to be treated are adsorbed to the metal ion adsorbent, the adsorbent is separated from the liquid to be treated, metal ions are moved from the separated adsorbent into the recovery liquid, and metal ions are A metal recovery method, wherein the separated adsorbent is separated from the recovered liquid, and the recovered liquid is evaporated to recover the metal. The metal recovery method according to claim 6, wherein the adsorbent separated from the recovery liquid is reused.