Self-reactive prussian blue material and production method therefor

Abstract

The present invention relates to a self-reactive Prussian blue material and a production method therefor, in which a separate magnetic synthesis process and an additional process of coating a Prussian blue material are not necessary. To this end, the present invention provides a self-reactive Prussian blue material in which a unit cell has a face-centered cubic (FCC) structure, bonds of water molecules present on branches of the lattice rebind with contaminants containing cesium ions, thereby enabling the contaminants to be adsorbed on the lattice structure by chemical adsorption, and a magnetic particle element and a Prussian blue material phase are simultaneously observed while the self-reactive Prussian blue material has an insoluble structure with respect to a solution containing the contaminants.

Description

Magnetically reactive Prussian blue substance and method for producing the same

[0001] The present invention relates to a magnetically responsive Prussian blue material and a method for producing the same. More particularly, the present invention relates to a magnetically responsive Prussian blue material and a method for producing the same, which do not require a separate magnetic material synthesis process and an additional process for coating the Prussian blue material.

[0002] South Korea has operated nuclear power plants since the 1970s, and while this has contributed significantly to the current climate of increasing energy consumption and reducing carbon emissions, significant amounts of spent nuclear fuel continue to accumulate each year at operating nuclear power plants.

[0003] In the case of waste generated from nuclear power generation, there are difficulties in obtaining consent from local residents to build a separate waste disposal facility, so the waste is currently stored in a shielded manner near the nuclear power plant.

[0004] The accumulated amount of waste stored in temporary storage facilities within nuclear power plants is nearly saturated compared to the total storage capacity, requiring an alternative method for handling spent nuclear fuel.

[0005] Prior art document: KR Patent Publication No. 10-097677 (announced on August 12, 2010)

[0006] The present invention has been devised to solve the above problems, and in particular, it is intended to provide a self-reactive Prussian blue material and a method for producing the same, which can adsorb and recover radioactive contaminants including cesium, while being suitable for mass production and which can be expected to reduce costs and improve efficiency.

[0007] In order to achieve the above object, a magnetically responsive Prussian blue material according to an embodiment of the present invention is characterized in that the unit cell has a face-centered cubic (FCC) structure, the bonds of water molecules existing in the lattice branches can recombine with contaminants including cesium ions, and the contaminants can be adsorbed to the lattice structure by chemical adsorption, and the magnetic particle element and the Prussian blue material phase are observed simultaneously while having an insoluble structure with respect to a solution containing the contaminants.

[0008] In addition, the self-reactive Prussian blue material according to an embodiment of the present invention is characterized in that the phase analysis result includes Fe4(Fe(CN)6)3.

[0009] Additionally, the self-responsive Prussian blue material according to an embodiment of the present invention may include at least one of transition element ions including separate iron (Fe) ions, yttrium (Y) ions, strontium (Sr) ions, cobalt (Co) ions, and barium (Ba) ions.

[0010] Additionally, the self-reactive Prussian blue material according to an embodiment of the present invention may contain Fe4(Fe(CN)6)3 as a phase analysis result, but may not contain any of the transition elements including yttrium (Y), strontium (Sr), cobalt (Co), and barium (Ba) in the product.

[0011] In addition, the self-reactive Prussian blue material according to an embodiment of the present invention may not require the addition of acids including citric acid (C6H8O7), trisodium citrate (Na3C6H5O7), and hydrochloric acid (HCl) in a liquid chemical process.

[0012] In addition, the self-reactive Prussian blue material according to an embodiment of the present invention shows a tendency to steadily increase although the rate of increase in the pollutant adsorption efficiency decreases as the initial concentration of the pollutant solution containing cesium ions increases compared to when the initial concentration of the pollutant solution containing cesium ions is small, and can exhibit an adsorption efficiency of 100% at a specific input amount.

[0013] A method for producing a self-reactive Prussian blue material according to an embodiment of the present invention is characterized by producing a self-reactive Prussian blue powder by mixing a Prussian blue solution into a yttrium iron oxide precursor solution to produce a mixed solution and then drying the mixed solution.

[0014] A method for producing a self-reactive Prussian blue material according to an embodiment of the present invention comprises the steps of (a) preparing a mixed solution by adding an acid to ultrapure water; (b) dissolving and mixing a metal precursor and an iron precursor in the resultant of step (a); (c) dissolving and mixing a Prussian blue precursor in the resultant of step (b); and (d) waiting until an auto-combustion reaction occurs in the resultant of step (c) and then obtaining self-reactive Prussian blue particles.

[0015] Additionally, the acid in step (a) may include citric acid (C6H8O7) or trisodium citrate (Na3C6H5O7).

[0016] In addition, the metal precursors of step (b) are yttrium nitrate (Y(NO3)3·xH2O), yttrium calbonate (Y2(CO3)3·xH2O), yttrium sulfate (Y2(SO4)3·xH2O), strontium nitrate (Sr(NO3)2·xH2O), strontium calbonate (SrCO3·xH2O), strontium sulfate (SrSO4·xH2O), barium nitrate (Ba(NO3)2·xH2O), barium carbonate (Barium calbonate (BaCO3·xH2O), barium sulfate (BaSO4·xH2O), It may include at least one of cobalt nitrate (Co(NO3)3·xH2O), cobalt calbonate (Co2(CO3)3·xH2O), and cobalt sulfate (Co2(SO4)3·xH2O).

[0017] Additionally, the iron precursor of step (b) may include at least one of iron chloride (FeCl3·xH2O), iron nitrate (Fe(NO3)3·xH2O), and iron sulfate (FeSO4·xH2O).

[0018] In addition, the Prussian blue precursor of step (c) is potassium ferrocyanide (Ferrocyanide, [Fe(CN)6] 4- ) may be included.

[0019] In addition, a method for producing a self-reactive Prussian blue material that does not contain a transition element other than iron according to another embodiment of the present invention comprises the steps of (a) dissolving and mixing an iron precursor in ultrapure water; (b) dissolving and mixing a Prussian blue precursor in the resultant product of step (a); and (c) waiting until an autocombustion reaction occurs in the resultant product of step (b) and then obtaining self-reactive Prussian blue particles.

[0020] According to the present invention, there is an effect of being able to separate radioactive contaminants, including cesium ions, in an adsorbed state.

[0021] In addition, according to the present invention, there is no need for a separate process for synthesizing a nano-sized magnetic body, and there is no need for an additional process for coating the synthesized magnetic body with Prussian blue.

[0022] In addition, according to the present invention, since it uses a liquid chemical reaction process, it is suitable for mass production and has high cost efficiency, has a high recovery rate compared to the input material, does not require expensive equipment to maintain constant temperature and pressure throughout the entire material synthesis process, and has no risk of environmental pollution due to wastewater generation because there is no coating process.

[0023] In addition, according to the present invention, there is an effect of maximizing the yield through quantitative input according to the chemical formula.

[0024] In addition, according to the present invention, since metal precursors of transition elements including yttrium, strontium, cobalt, and barium and acids such as citric acid and hydrochloric acid are not added in the liquid chemical reaction process, cost reduction is possible, and compared to examples in which metal precursors and acids are added, there is an effect of obtaining superior magnetic properties and adsorption rates.

[0025] Figure 1 is a photograph showing the optical results of the self-reactive Prussian blue according to the present invention.

[0026] Figure 2 is a photograph showing how the magnetically reactive Prussian blue according to the present invention reacts to an external magnetic field.

[0027] Figure 3 is a graph showing the results of phase analysis of self-reactive Prussian blue according to the first embodiment of the present invention.

[0028] Figure 4 is a diagram showing the lattice structure of soluble Prussian blue and insoluble Prussian blue.

[0029] Figure 5 is a conceptual diagram illustrating a liquid chemical reaction process, which is a method for producing self-reactive Prussian blue according to the first embodiment of the present invention.

[0030] Figure 6 is a diagram showing the RGB code of magnetically reactive Prussian blue particles containing yttrium ions.

[0031] Figure 7 is a graph showing the cesium adsorption efficiency according to the amount of self-reactive Prussian blue particles introduced according to the first embodiment of the present invention.

[0032] FIG. 8 is a graph showing the cesium adsorption efficiency according to the ratio (concentration) of the self-reactive Prussian blue particles introduced according to the first embodiment of the present invention.

[0033] Figure 9 is a graph comparing the results of phase analysis of self-reactive Prussian blue according to the first and second embodiments of the present invention.

[0034] Figure 10 is a conceptual diagram illustrating a liquid chemical reaction process, which is a method for producing self-reactive Prussian blue according to the second embodiment of the present invention.

[0035] Figure 11 is a graph comparing the magnetic properties of the magnetically reactive Prussian blue particle material obtained in the first and second embodiments of the present invention.

[0036] Figure 12 is a graph showing the results of a cesium adsorption experiment conducted under the same conditions for the first and second embodiments of the present invention and various comparative examples.

[0037] The magnetically reactive Prussian blue material according to an embodiment of the present invention is characterized in that the unit cell has a face-centered cubic (FCC) structure, the bonds of water molecules existing in the lattice branches can recombine with contaminants including cesium ions, and the contaminants can be adsorbed to the lattice structure by chemical adsorption, and the material has an insoluble structure with respect to a solution containing the contaminants, while the magnetic particle element and the Prussian blue material phase are observed simultaneously.

[0038] Prussian blue is used as a blue dye and as a medicine that can be taken in case of exposure to radioactive cesium.

[0039] Prussian blue as a blue dye has a structure that is soluble in water, and Prussian blue as a radioactive cesium treatment agent has a structure that is insoluble in water.

[0040] Prussian blue is suitable for capturing cesium ions due to its molecular structure.

[0041] Prussian blue has a lattice structure, with spaces within the lattice measuring 1.6 Å in diameter. The diameter of a cesium ion is 1.19 Å, which is large enough to be trapped within the Prussian blue lattice.

[0042] Although Prussian blue material has properties suitable for cesium adsorption, it is difficult to use it in actual industry.

[0043] Even if cesium is adsorbed, soluble Prussian blue cannot be recovered, making proper disposal of radioactive material impossible. Meanwhile, insoluble Prussian blue must wait for gravity to settle to the bottom for recovery.

[0044] To improve this, a method utilizing magnetic properties has been introduced. The principle is to coat the surface of a magnetic material with Prussian blue particles. This method causes the Prussian blue particles, which adsorb cesium, to gather in the direction of the external magnetic field, effectively removing only the Prussian blue particles needed for radioactive treatment from contaminated materials.

[0045] However, manufacturing coated Prussian blue requires a separate process for synthesizing nano-sized magnetic materials. These synthesized magnetic materials are then added to a Prussian blue solution for coating. However, coating is not suitable for mass production and is cost-effective. Furthermore, the recovery rate is low compared to the amount of material used, and there are limitations such as the requirement to maintain constant temperature and pressure throughout the entire material synthesis process. Furthermore, the wastewater generated after the coating process poses a risk of environmental pollution.

[0046] The present invention proposes another method for imparting magnetic properties to Prussian blue particles. The method for producing magnetically reactive Prussian blue according to the present invention utilizes both a material capable of synthesizing iron oxide and a material capable of synthesizing Prussian blue, thereby eliminating the need for a separate synthesis of a magnetic material and a coating process, unlike the aforementioned method for producing coated Prussian blue.

[0047] As a result of analyzing the magnetically reactive Prussian blue material produced by the magnetically reactive Prussian blue production method according to the present invention, it was confirmed that the magnetic iron oxide and Prussian blue material phases were observed simultaneously.

[0048] In addition, 0.002 g of the magnetically reactive Prussian blue according to the present invention was added to 20 ml of a solution having an initial cesium concentration of 187 ppm, and an external magnetic field was applied 24 hours later to remove only the magnetically reactive Prussian blue. The cesium concentration of the remaining solution was measured, confirming that cesium adsorption was possible.

[0049] The magnetically reactive Prussian blue material according to the present invention has a face-centered cubic (FCC) structure as a unit cell, and the bonds of water molecules existing in the lattice branches can recombine with contaminants including cesium ions to adsorb the contaminants into the lattice structure through chemical adsorption, and has a structure that is insoluble in a solution containing the contaminants, while having the characteristics of simultaneously observing the magnetic particle element and the Prussian blue material phase.

[0050] In addition, the self-reactive Prussian blue material according to the second embodiment of the present invention has a characteristic that the phase analysis result includes Fe4(Fe(CN)6)3, but the product does not include any of the transition elements including yttrium (Y), strontium (Sr), cobalt (Co), and barium (Ba).

[0051] In addition, since the manufacturing process does not include a process of coating Prussian blue on magnetic particles, when the final material is observed after manufacturing using a SEM (Scanning electron microscope), etc., it exhibits a different structure from the structure in which Prussian blue particles are uniformly coated on the surface of magnetic particles as in the conventional coating process described above, and a structure in which Prussian blue particles and magnetic particles are integrated is also observed.

[0052] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. First, when assigning reference numerals to components in each drawing, it should be noted that identical components are assigned the same numerals as much as possible even if they are shown in different drawings. Furthermore, in describing the present invention, if a detailed description of a related known structure or function is judged to obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, although preferred embodiments of the present invention will be described below, it should be understood that the technical idea of ​​the present invention is not limited thereto and can be modified and implemented in various ways by those skilled in the art.

[0053] Fig. 1 is a photograph showing the optical results of the magnetically reactive Prussian blue according to the present invention, and Fig. 2 is a photograph showing the magnetically reactive Prussian blue according to the present invention reacting to an external magnetic field.

[0054] Referring to Fig. 1, a clear color change can be observed in the newly synthesized Prussian Blue-magnetic adsorption recovery agent (Y-Fe-PB powder) on the left, which is distinguished in color from the control group (Y-Fe powder) on the right (PB = Prussian Blue, Y-Fe = Yttrium Iron oxide).

[0055] Referring to Figure 2, a neodymium (Nd) magnet was used as an external magnetic field, and it can be confirmed that the magnetically reactive Prussian blue powder that adsorbed cesium ions was attracted to the magnet and accumulated.

[0056] FIG. 3 is a graph showing the results of phase analysis of self-reactive Prussian blue according to the first embodiment of the present invention.

[0057] In Fig. 3, the upper graph is the XRD measurement result of Fe4(Fe(CN)6)3, which is the target material to be produced in the present invention, and the lower graph is the XRD measurement result of the self-responsive Prussian material actually produced in the present invention.

[0058] Comparing the two graphs, it can be confirmed that the phase of the self-responsive Prussian material produced in the present invention actually includes the results shown in the phase analysis of Fe4(Fe(CN)6)3.

[0059] This means that the self-reactive Prussian material actually produced in the present invention has an insoluble structure and is capable of chemical adsorption.

[0060] Figure 4 is a diagram showing the lattice structure of soluble Prussian blue and insoluble Prussian blue.

[0061] In Figure 4, the left side is an insoluble structure, and the right side is a soluble structure.

[0062] The soluble structure on the right is K adsorbed in the lattice structure. + and Cs + and Ti + These can be substituted for each other and adsorb contaminants (cesium ions) into the lattice structure (physical adsorption). However, since this is a soluble structure, it is difficult to separate the magnetic material to which the contaminants have been adsorbed.

[0063] On the other hand, the insoluble structure on the left is Cs, where the bonds of water molecules existing in the lattice branches + and Ti + By recombination, contaminants (cesium ions) can be adsorbed into the lattice structure (chemical adsorption). Since this is an insoluble structure, the magnetic material to which contaminants have been adsorbed can be easily collected simply by applying an external magnetic field without precipitating the solution.

[0064] The chemical reaction formula to be derived in the present invention is as follows.

[0065] 4FeCl3+ 3K4Fe(CN)6→ Fe4(Fe(CN)6)3+ 12KCl

[0066] The product, Fe4(Fe(CN)6)3, is a magnetically reactive Prussian blue substance with an insoluble structure, and can separate contaminants using an external magnetic field due to the chemical adsorption mechanism.

[0067] FIG. 5 is a conceptual diagram illustrating a liquid chemical reaction process, which is a method for producing self-reactive Prussian blue according to the first embodiment of the present invention.

[0068] Referring to Figure 5, it can be seen that a separate magnetic material (iron oxide) synthesis process is eliminated, and the additional process of coating the iron oxide with Prussian blue material is also unnecessary. Furthermore, expensive equipment, such as a hydrothermal synthesis device, is not required to maintain constant temperature and pressure throughout the entire material synthesis process.

[0069] When a Prussian blue solution is mixed with a Y-Fe solution to produce a mixed solution and then dried, a magnetically reactive Prussian blue powder is produced. As mentioned above, the magnetically reactive Prussian blue produced in this way corresponds to Fe4(Fe(CN)6)3 based on the optical results of Fig. 1, the magnetic field response results of Fig. 2, and the phase analysis results of Fig. 3.

[0070] In Fig. 5, a Y-Fe solution is described as an example of a reactant, but in addition to yttrium (Y) ions, other transition elements that can improve magnetic properties, such as divalent cations or trivalent cations such as Fe, Sr, Co, and Ba, can be applied, and the type of transition element is not limited here.

[0071] A method for producing a magnetically reactive Prussian blue material according to a first embodiment of the present invention comprises the steps of (a) preparing a mixed solution by adding an acid to ultrapure water; (b) dissolving and mixing a metal precursor and an iron precursor in the resultant of step (a); (c) dissolving and mixing a Prussian blue precursor in the resultant of step (b); and (d) waiting until an autocombustion reaction occurs in the resultant of step (c) and then obtaining magnetically reactive Prussian blue particles. The above method does not include a step of separately coating Prussian blue on magnetic particles.

[0072] Here, the acid in step (a) includes citric acid (C6H8O7) or trisodium citrate (Na3C6H5O7), but is not limited thereto, and any acid commonly used in the relevant field can be used without limitation.

[0073] In addition, the metal precursors of step (b) are yttrium nitrate (Y(NO3)3·xH2O), yttrium calbonate (Y2(CO3)3·xH2O), yttrium sulfate (Y2(SO4)3·xH2O), strontium nitrate (Sr(NO3)2·xH2O), strontium calbonate (SrCO3·xH2O), strontium sulfate (SrSO4·xH2O), barium nitrate (Ba(NO3)2·xH2O), barium carbonate (Barium calbonate (BaCO3·xH2O), barium sulfate (BaSO4·xH2O), It includes at least one of cobalt nitrate (Co(NO3)3·xH2O), cobalt calbonate (Co2(CO3)3·xH2O), and cobalt sulfate (Co2(SO4)3·xH2O), but is not limited thereto, and any acid commonly used in the relevant field may be used without limitation.

[0074] In addition, the iron precursor of step (b) includes at least one of iron chloride (FeCl3·xH2O), iron nitrate (Fe(NO3)3·xH2O), and iron sulfate (FeSO4·xH2O), but is not limited thereto, and any acid commonly used in the relevant field may be used without limitation.

[0075] In addition, the Prussian blue precursor of step (c) is potassium ferrocyanide (Ferrocyanide, [Fe(CN)6] 4- ) and can be used without limitation as long as it is an acid commonly used in the field.

[0076] Hereinafter, an example (first example) for a method for producing a magnetically reactive Prussian blue containing yttrium ions is described.

[0077] First embodiment

[0078] Preparation of magnetically reactive Prussian blue containing yttrium ions

[0079] (1) Dissolve and mix citric acid (C6H8O7) in 200 ml of ultrapure water (DI water) at a concentration of 0.096 M.

[0080] (2) After 4 hours, yttrium nitrate (Y(NO3)3·6H2O), iron nitrate (Fe(NO3)3·9H2O), and iron chloride (FeCl3) are dissolved and mixed at concentrations of 0.036M, 0.060M, and 0.020M, respectively.

[0081] (3) After 4 hours, potassium ferrocyanide (K4[Fe(CN)6]·3H2O) and hydrochloric acid (HCl) are dissolved and mixed at concentrations of 0.020 M and 0.088 M, respectively.

[0082] (4) After dissolving at high speed for 2 hours, wait until the auto-combustion reaction occurs at a temperature of 80℃.

[0083] (5) As a result, about 10 g of magnetically reactive Prussian blue particles can be obtained, and a larger amount of particles can be obtained if the concentration ratio is correct.

[0084] Figure 6 is a diagram showing the RGB code of magnetically reactive Prussian blue particles containing yttrium ions.

[0085] Referring to Figure 6, it can be seen that the G and B values ​​are relatively high, and the B value in particular is high.

[0086] Radioactive cesium adsorption effect experiment

[0087] In order to confirm the possibility and effect of cesium adsorption of the self-reactive Prussian blue material according to the first embodiment of the present invention, an experiment was conducted as follows.

[0088] (1) After determining the target cesium concentration, prepare a cesium solution of that concentration.

[0089] (2) Divide the prepared cesium solution into n equal parts, add the magnetically reactive Prussian blue particles according to the present invention, and mix for 24 hours or more.

[0090] (3) By providing an external magnetic field to the mixed solution for more than 24 hours, only the magnetically reactive Prussian blue particles to which cesium ions are adsorbed are separated.

[0091] (4) The concentration of the cesium solution from which the magnetically reactive Prussian blue particles adsorbed with cesium ions have been removed is measured.

[0092] (5) Calculate the adsorption efficiency using the initial and final concentrations of the cesium solution.

[0093] At this time, the concentration of the cesium solution was measured using ICP-MS, but of course, other equipment for measuring concentration can be used.

[0094] After adding 0.002 g of the self-reactive Prussian blue particles manufactured according to the first example to a 20 ml cesium solution, the cesium adsorption efficiency was confirmed, and the following results were obtained.

[0095] Prepared cesium solution (initial concentration) Example 1 (later concentration) Concentration (ppm) 189 166 Adsorption efficiency (%) - 12.16

[0096] Referring to Table 1, it can be confirmed that the concentration of cesium ions decreases after the magnetically reactive Prussian blue particles manufactured in the first example are introduced.

[0097] Figure 7 is a graph showing the cesium adsorption efficiency according to the amount of magnetically reactive Prussian blue particles introduced according to the first embodiment of the present invention. In Figure 7, the horizontal axis represents the amount of magnetically reactive Prussian blue particles introduced (g), and the vertical axis represents the cesium adsorption efficiency (%).

[0098] The graph in Fig. 7 illustrates the results according to an example containing yttrium ions. In Fig. 7, the initial concentrations of the cesium solution correspond to 10, 187, and 700 ppm, respectively, in black (sample 1), red (sample 2), and green (sample 3).

[0099] Referring to Fig. 7, when the initial concentration of the cesium solution is relatively low, such as 10 ppm, the cesium adsorption efficiency is very high even when a small amount of self-reactive Prussian blue is added, and as the amount added increases, the cesium adsorption efficiency shows a tendency to increase rapidly. When the amount of self-reactive Prussian blue added becomes 0.125 g, the cesium adsorption efficiency reaches 100%, and even if the amount added thereafter is increased, the cesium adsorption efficiency is maintained at 100%.

[0100] In addition, in the case of sample 2, the increase rate of cesium adsorption efficiency according to the increase in the amount of self-reactive Prussian blue added is smaller than that of sample 1, but it shows a steady increasing trend, and it can be seen that the cesium adsorption efficiency exceeds 90% when 0.5 g is added.

[0101] In addition, in the case of sample 3, the increase rate of cesium adsorption efficiency according to the increase in the amount of self-reactive Prussian blue added is smaller than that of sample 2, but it shows a steady increasing trend, and it can be confirmed that the cesium adsorption efficiency is close to 50% when 0.5 g is added.

[0102] FIG. 8 is a graph showing the cesium adsorption efficiency according to the ratio (concentration) of the magnetically reactive Prussian blue particles added according to the first embodiment of the present invention. In FIG. 8, the horizontal axis of the left graph is a logarithmic scale when the concentration of the magnetically reactive Prussian blue particles is expressed in mg / L, and the horizontal axis of the right graph is a logarithmic scale when the concentration of the magnetically reactive Prussian blue particles is expressed in mg / ppm.

[0103] The graph of Fig. 8 also shows the results according to an example including yttrium ions, and in Fig. 8, the initial concentrations of the cesium solution correspond to 0.001, 0.1, 10, and 1000 ppm in the order of black (sample 4), red (sample 5), green (sample 6), and blue (sample 7), respectively.

[0104] Referring to Fig. 8, it can be confirmed that the input concentration of self-reactive Prussian blue particles to reach 100% cesium adsorption efficiency is relatively low for sample 4, and that the input concentration of self-reactive Prussian blue particles to reach 100% cesium adsorption efficiency gradually increases from sample 5 to sample 7. In other words, it can be confirmed that by increasing the input concentration of self-reactive Prussian blue particles, an adsorption efficiency of 100% can be achieved even if the initial concentration of the cesium solution is high.

[0105] FIG. 9 is a graph comparing the results of phase analysis of self-reactive Prussian blue according to the first and second embodiments of the present invention.

[0106] In Fig. 9, the left graph is the XRD measurement result of the self-responsive Prussian material (Y-Fe-PB) manufactured in the first embodiment, and the right graph is the XRD measurement result of the self-responsive Prussian blue material (Fe-PB) manufactured in the second embodiment (PB = Prussian Blue, Y-Fe = Yttrium Iron oxide).

[0107] The input materials used in Example 1 and the input materials used in Example 2 are compared in Table 2 below.

[0108] Progress #Input materials First embodiment (Y-Fe-PB) Second embodiment (Fe-PB) 1 D.I. water ooC6H8O7ox2 D.I. water + FeCl3 ooFe(NO3)3·9H2OooY(NO3)3·6H2Oox3K4(Fe(CN)6)·3H2OooHClox

[0109] Referring to Table 2, it can be confirmed that the second embodiment excluded the metal precursor and acid used in the first embodiment. As a result, it can be confirmed that the manufacturing cost per unit weight of the self-reactive Prussian blue material was significantly reduced, as shown in Table 3 below.

[0110] Example 1 (Y-Fe-PB) Example 2 (Fe-PB) Price per amount (won / g) 4,755.63,053.1

[0111] Referring to Tables 2 and 3, in the second embodiment, advanced self-responsive Prussian blue particles were realized at a cost of approximately 64% of the existing unit cost under a simplified process compared to the first embodiment. Referring to Fig. 9, it can be confirmed that the second embodiment can synthesize a self-responsive Prussian blue material of the same phase by removing the amorphous phase that existed in the first embodiment and using a simplified raw material. Since the target material to be created in the first and second embodiments, Fe4(Fe(CN)6)3, appears in the XRD measurement results, it can be seen that the self-responsive Prussian material actually created in the second embodiment can be chemically adsorbed with an insoluble structure, just like the first embodiment.

[0112] FIG. 10 is a conceptual diagram illustrating a liquid chemical reaction process, which is a method for producing self-reactive Prussian blue according to a second embodiment of the present invention.

[0113] Referring to Figure 10, it can be seen that a separate magnetic material (iron oxide) synthesis process is eliminated, and the additional process of coating the iron oxide with Prussian blue material is also unnecessary. Furthermore, expensive equipment, such as a hydrothermal synthesis device, is not required to maintain constant temperature and pressure throughout the entire material synthesis process.

[0114] When a Prussian blue solution is mixed with an Fe solution to produce a mixed solution and then dried, a magnetically reactive Prussian blue powder is produced. As mentioned above, the magnetically reactive Prussian blue produced in this way corresponds to Fe4(Fe(CN)6)3 based on the optical results of Fig. 1 and the phase analysis results of Fig. 9.

[0115] A method for producing a self-reactive Prussian blue material according to a second embodiment of the present invention comprises the steps of (a) dissolving and mixing an iron precursor in ultrapure water; (b) dissolving and mixing a Prussian blue precursor in the resultant product of step (a); and (c) waiting until an autocombustion reaction occurs in the resultant product of step (b) and then obtaining self-reactive Prussian blue particles.

[0116] The above manufacturing method does not include a process of separately coating Prussian blue on magnetic particles.

[0117] In addition, in the above manufacturing method, yttrium nitrate (Yttrium nitrate, Y(NO3)3·xH2O), yttrium calbonate (Y2(CO3)3·xH2O), yttrium sulfate (Y2(SO4)3·xH2O), strontium nitrate (Sr(NO3)2·xH2O), strontium calbonate (SrCO3·xH2O), strontium sulfate (SrSO4·xH2O), barium nitrate (Ba(NO3)2·xH2O), barium carbonate (Barium calbonate, BaCO3·xH2O), barium sulfate (Barium sulfate, BaSO4·xH2O), Metal precursors such as cobalt nitrate (Co(NO3)3·xH2O), cobalt calbonate (Co2(CO3)3·xH2O), and cobalt sulfate (Co2(SO4)3·xH2O) are not added.

[0118] Additionally, in the above manufacturing method, acids such as citric acid (C6H8O7), trisodium citrate (Na3C6H5O7), and hydrochloric acid (HCl) are not added.

[0119] In addition, the iron precursor of step (a) includes at least one of iron chloride (FeCl3·xH2O), iron nitrate (Fe(NO3)3·xH2O), and iron sulfate (FeSO4·xH2O), but is not limited thereto, and any acid commonly used in the relevant field may be used without limitation.

[0120] In addition, the Prussian blue precursor of step (b) is potassium ferrocyanide (Ferrocyanide, [Fe(CN)6] 4-) and can be used without limitation as long as it is an acid commonly used in the field.

[0121] Hereinafter, an example (second example) of a method for producing self-reactive Prussian blue that does not contain a transition element other than iron is described.

[0122] Second embodiment

[0123] Preparation of magnetically reactive Prussian blue containing no transition elements other than iron

[0124] (1) Dissolve and mix iron nitrate (Fe(NO3)3·9H2O) and iron chloride (FeCl3) in 200 ml of ultrapure water (DI water) at concentrations of 0.06 M and 0.24 M, respectively.

[0125] (2) After 4 hours, potassium ferrocyanide (K4[Fe(CN)6]·3H2O) is dissolved and mixed at a concentration of 0.18 M each.

[0126] (3) After dissolving at high speed for 2 hours, wait until the auto-combustion reaction occurs at a temperature of 80℃.

[0127] Table 4 below shows the types and concentrations of substances used in the first and second embodiments.

[0128] Progress #Input materials Example 1 (Y-Fe-PB) Example 2 (Fe-PB) 1 D.I. water 200ml 200ml C6H8O7 0.96M 2 D.I. water + FeCl 3 0.02M 0.24MFe(NO3)3·9H2O 0.06M 0.06M Y(NO3)3·6H2O 0.36M 3 K4(Fe(CN)6)·3H2O 0.02M 0.18MHCl 0.088M

[0129] Figure 11 is a graph comparing the magnetic properties of the magnetically responsive Prussian blue particle material obtained in the first and second embodiments of the present invention.

[0130] Referring to Fig. 11, the process of the second embodiment proceeds similarly to the first embodiment, but some of the input of raw materials is omitted, but it can be confirmed that the magnetic properties of the second embodiment are improved compared to the first embodiment.

[0131] Table 5 below shows the magnetic properties of the first and second embodiments.

[0132] Example 1 (Y-Fe-PB) Example 2 (Fe-PB) Saturation magnetization|(M s , emu / g)2.349.91Remanence magnetization(M r , emu / g)0.242.18Coercivity(H c , Oe)47.61146.98

[0133] Referring to Table 5, it can be confirmed that the magnetically responsive Prussian blue material according to the second embodiment of the present invention has a saturation magnetization of 9 emu / g or more, a remanence magnetization of 2 emu / g or more, and a coercivity of 140 Oe or more.

[0134] Radioactive cesium adsorption effect experiment

[0135] In order to confirm the possibility and effect of cesium adsorption of the self-reactive Prussian blue material according to the second embodiment of the present invention, an experiment was conducted as follows.

[0136] (1) After determining the target cesium concentration, prepare a cesium solution of that concentration.

[0137] (2) Divide the prepared cesium solution into n equal parts, add the magnetically reactive Prussian blue particles according to the present invention, and mix for 24 hours or more.

[0138] (3) By providing an external magnetic field to the mixed solution for more than 24 hours, only the magnetically reactive Prussian blue particles to which cesium ions are adsorbed are separated.

[0139] (4) The concentration of the cesium solution from which the magnetically reactive Prussian blue particles adsorbed with cesium ions have been removed is measured.

[0140] (5) Calculate the adsorption efficiency using the initial and final concentrations of the cesium solution.

[0141] At this time, the concentration of the cesium solution was measured using ICP-MS, but of course, other equipment for measuring concentration can be used.

[0142] For comparison, the initial cesium concentration (ppm), measured concentration (ppm) after cesium adsorption treatment, and adsorption rate (%) calculated using the initial concentration and measured concentration for each case of the first embodiment (Y-Fe-PB) and normal Prussian blue (Normal PB), the case where Prussian blue was omitted in the first embodiment (Y-Fe), and the second embodiment (Fe-PB) are shown in Table 6 below.

[0143] Y-Fe-PBNormal PBY-FeFe-PBInitial concentration (ppm)54.6Measured concentration (ppm)14.230.253.70.317Adsorption rate (%)73.9944.691.6599.42

[0144] FIG. 12 is a graph showing the results of a cesium adsorption experiment conducted under the same conditions for the first and second embodiments of the present invention and various comparative examples. Referring to FIG. 12 and Table 6, it can be confirmed that the self-reactive Prussian blue material according to the second embodiment shows an excellent adsorption rate (99.42%) even when compared with the normal Prussian blue (Normal PB), the case where Prussian blue is omitted in the first embodiment (Y-PB), and even the first embodiment including yttrium ions (Y-Fe-PB).

[0145] The fact that the general Prussian blue showed an adsorption rate of 44.69% seems to be because the soluble and insoluble substances were mixed, so not all of the Prussian blue present in the sample could be removed.

[0146] The above description is merely an illustrative description of the technical idea of ​​the present invention, and those skilled in the art will appreciate that various modifications, changes, and substitutions may be made without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention and the accompanying drawings are not intended to limit the technical idea of ​​the present invention, but rather to explain it, and the scope of the technical idea of ​​the present invention is not limited by these embodiments and the accompanying drawings. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present invention.

[0147] The present invention can be used in industries that remove radioactive contaminants including cesium.

Claims

1. The unit cell is a face-centered cubic (FCC) structure, The bonds of water molecules existing in the lattice branches can recombine with contaminants including cesium ions, and contaminants can be adsorbed to the lattice structure through chemical adsorption. A magnetically reactive Prussian blue material having an insoluble structure in a solution containing contaminants, in which both magnetic particle elements and Prussian blue material phases are observed simultaneously.

2. In paragraph 1, A magnetically reactive Prussian blue material containing Fe4(Fe(CN)6)3 as determined by phase analysis.

3. In paragraph 1, A magnetically reactive Prussian blue material comprising at least one transition element ion comprising a separate iron (Fe) ion, a yttrium (Y) ion, a strontium (Sr) ion, a cobalt (Co) ion, and a barium (Ba) ion.

4. In paragraph 1, A magnetically reactive Prussian blue material, the phase analysis of which shows that the product contains Fe4(Fe(CN)6)3, but does not contain any of the transition elements including yttrium (Y), strontium (Sr), cobalt (Co), and barium (Ba).

5. In paragraph 1, A self-reactive Prussian blue substance that does not require the addition of acids, including citric acid (C6H8O7), trisodium citrate (Na3C6H5O7), and hydrochloric acid (HCl), in liquid chemical processes.

6. In paragraph 1, A self-reactive Prussian blue substance that exhibits an adsorption efficiency of 100% at a specific amount of input, and although the rate of increase in the adsorption efficiency of pollutants decreases as the initial concentration of the pollutant solution containing cesium ions increases compared to when the initial concentration is small, it exhibits a tendency to steadily increase.

7. A method for producing self-reactive Prussian blue, which comprises mixing a Prussian blue solution into a yttrium iron oxide precursor solution to produce a mixed solution, and then drying the mixed solution to produce self-reactive Prussian blue powder. 8.(a) A step of preparing a mixed solution by adding acid to ultrapure water; (b) a step of dissolving and mixing a metal precursor and an iron precursor in the resultant product of step (a); (c) a step of dissolving and mixing a Prussian blue precursor into the resultant product of step (b); and (d) a step of obtaining self-reactive Prussian blue particles after waiting for an auto-combustion reaction to occur in the result of step (c). A method for producing a magnetically reactive Prussian blue material comprising:

9. In paragraph 8, (a) A method for producing a self-reactive Prussian blue substance, wherein the acid in step (a) comprises citric acid (C6H8O7) or trisodium citrate (Na3C6H5O7).

10. In paragraph 8, (b) The metal precursors of step are yttrium nitrate (Y(NO3)3·xH2O), yttrium calbonate (Y2(CO3)3·xH2O), yttrium sulfate (Y2(SO4)3·xH2O), strontium nitrate (Sr(NO3)2·xH2O), strontium calbonate (SrCO3·xH2O), strontium sulfate (SrSO4·xH2O), barium nitrate (Ba(NO3)2·xH2O), barium carbonate (Barium calbonate (BaCO3·xH2O), barium sulfate (BaSO4·xH2O), A method for producing a self-reactive Prussian blue material, comprising at least one of cobalt nitrate (Co(NO3)3·xH2O), cobalt calbonate (Co2(CO3)3·xH2O), and cobalt sulfate (Co2(SO4)3·xH2O).

11. In paragraph 8, (b) A method for producing a self-reactive Prussian blue material, wherein the iron precursor of step (b) comprises at least one of iron chloride (FeCl3·xH2O), iron nitrate (Fe(NO3)3·xH2O), and iron sulfate (FeSO4·xH2O).

12. In paragraph 8, (c) The Prussian blue precursor in step (c) is potassium ferrocyanide ([Fe(CN)6] 4- ) for producing a self-reactive Prussian blue substance. 13.(a) A step of dissolving and mixing an iron precursor in ultrapure water; (b) a step of dissolving and mixing a Prussian blue precursor into the resultant product of step (a); and (c) A method for producing a self-reactive Prussian blue material, comprising the step of obtaining self-reactive Prussian blue particles after waiting for an auto-combustion reaction to occur in the resultant product of step (b).

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