KR100839037B1 - Method for fabrication of granular zirconium nano-mesostructure and apparatus and method for regeneration of granular zirconium nano-mesostructure and recovery of phosphorus - Google Patents

Abstract

A method for manufacturing a granular zirconium mesostructure is provided to prevent an outflow of powder by changing a powdered mesostructure into a granular structure, and to solve fundamentally high pressure and short circuit problems within a reactor. A method for manufacturing a granular zirconium mesostructure includes the steps of: (S101) mixing 5-100 w/v% of acrylamide with an accelerator and a cross-linking agent to form a first mixture solution, wherein the accelerator increases a gelation rate of acrylamide, and the cross-linking agent links acrylamides with each other to form a network structure; (S102) mixing the first mixture solution with a powdered zirconium mesostructure to form a second mixture solution; (S103, S104) injecting a reaction initiator into the second mixture solution to form gel, wherein the reaction initiator initiates the transition of acrylamide to gel; and (S105) molding the gel into a predetermined size to form the granular zirconium mesostructure. Further, the accelerator is 3-(dimethylamino)propionitrile.

Description

Method for fabrication of granular zirconium nano-mesostructure and Apparatus and Method for regeneration of granular zirconium nano-mesostructure and recovery of phosphorus}

1 is a flow chart for explaining a method for producing a granular zirconium mesostructure according to an embodiment of the present invention.

Figure 2a is a photograph showing a mold for molding each of the granular zirconium mesostructures according to an embodiment of the present invention.

FIG. 2B is a photograph of a granular zirconium mesostructure formed by the mold of FIG. 2A. FIG.

FIG. 2C is a cross-sectional photograph of a granular zirconium mesostructure formed by the mold of FIG. 2A. FIG.

Figure 3 is a graph showing the effect of the pH of the granular zirconium mesostructure prepared according to an embodiment of the present invention.

Figure 4 is a graph showing a pseudo second-order equation according to the content of the powder zirconium mesostructures immobilized in acrylamide.

5 is a FE-SEM photograph showing the particle surface of the granular zirconium mesostructures according to the content of the powder zirconium mesostructures immobilized on acrylamide and the composition analysis results through EDS.

6 is a particle size analysis result of the granular zirconium meso structure prepared according to an embodiment of the present invention.

7 is a process chart for explaining the regeneration method of the granular zirconium meso structure and phosphorus recovery method according to the first embodiment of the present invention.

8A and 8B are reference diagrams showing a mechanism for regenerating a granular zirconium mesostructure and a method for recovering phosphorus according to a second embodiment of the present invention.

9 is an apparatus for regeneration and recovery of phosphorus electrochemical granular zirconium mesostructures according to an embodiment of the present invention.

The present invention relates to a method for producing granular zirconium mesostructures, and an apparatus and method for regenerating and recovering phosphorus of granular zirconium mesostructures.

The main methods for removing phosphorus in water are biological removal, flocculation-precipitation, crystallization, adsorption, etc. Among these methods, biological and flocculation-precipitation are widely used. However, in the biological removal method, the water quality after treatment is kept somewhat high at several mg P / L, and the low reliability of the treatment efficiency is mentioned as a problem.

To date, Biological Nutrient Removal (BNR) processes for sewage treatment consist of anaerobic tanks for nitrogen and phosphorus release, anoxic tanks to induce denitrification with internal return of nitric oxides, and aerobic tanks for nitrification. There are common methods and methods such as continuous flow type A2 / O, VIP, MUCT, 5-stage Bardenpho, and intermittent aeration depending on the process flow. However, these methods are not easy in terms of installation and maintenance because two or more reactors are connected in series and requires a large site area and requires a large number of auxiliary facilities.

In addition, the sequencing batch reactor (Sequencing Batch Reactor) is suitable for relatively small sewage treatment facilities as the inflow, reaction, precipitation, discharge, and rest processes are sequentially performed in a single reaction tank in accordance with a predetermined time sequence, but is the main equipment of the process. There is a disadvantage that the decanter which serves to discharge the treated water is expensive.

As a physicochemical treatment of phosphorus, flocculation-precipitation treatment using a flocculant has been widely used due to the simplicity and high efficiency of the process. In the flocculation-precipitation method, phosphorus may be removed to a low concentration, but a large amount of chemicals are required to achieve stable treatment efficiency, such that the operating cost increases. However, it is expensive to treat the generated waste sludge and there is no environmentally friendly treatment alternative to the disposal method.

The above biological removal method and flocculation-precipitation method all require a large installation area, and a large amount of sludge is generated, and the recovery and recycling of the removed phosphorus is difficult. The crystallization method can be used as a fertilizer because phosphorus in the water is removed as calcium hydroxyapatite, but there are few practical applications because complex pretreatment is required.

On the other hand, almost no sludge is generated in the zirconium meso structure in comparison with the above technique, and the removed phosphorus is most suitable as a treatment method aimed at highly processing-recycling because the removed phosphorus can be recycled. Unlike iron oxide, aluminum oxide, and zirconium oxide, zirconium mesostructures exhibit activity in the alkaline as well as acidic regions, thus requiring no additional pH adjustment and thus reducing maintenance costs. In addition, the installation area is reduced compared to other methods and does not require complicated pretreatment, and at the same time, it is relatively easy to maintain, so it may be applied to the treatment of effluents in small workplaces, river water or agricultural drainage of small loads.

Mesopores refer to medium pores between micropores and macropores and have a size of 2 to 50 nm. Mesoporous structures have been used extensively as adsorbents because of their uniform sized bubble arrays and high specific surface area. Zirconium has a high affinity (phosphory) for phosphorus and by forming meso-sized pores can maintain the reaction specific surface area higher than conventional adsorbents to improve the surface reaction efficiency.

Although zirconium mesostructures are adsorbents with high adsorption rates due to their high adsorption capacity, uniform size of pore arrays and specific surface area for phosphorus, no examples have been used in the field due to their powder structure. Powder structured zirconium mesostructures are not easy to handle, require high pressure during operation, and changeable adsorbents are shortened due to the differential flow phenomenon in which the influent flows only one side in the reactor due to suspended materials. There is a problem. In addition, the high production cost of the zirconium mesostructure of the powder structure acts as a limiting factor for commercial use.

The present invention has been made to solve the above problems, by changing the meso structure of the powder structure into a granular structure to prevent the outflow of the powder to be reused, thereby solving the problem of high pressure and short circuit in the reactor It is an object of the present invention to provide a method for producing a granular zirconium mesostructure that can be fundamentally solved.

In addition, the present invention regenerates the granular zirconium mesostructures that adsorbed phosphorus in water through physicochemical or electrochemical methods, and the effluent including the outflowed phosphorus can be reused in the form of phosphoric acid or potassium phosphate through an electrochemical reaction. It is an object of the present invention to provide an apparatus and method for regenerating and recovering phosphorus of zirconium mesostructures.

Method for producing a granular zirconium mesostructure according to the present invention for achieving the above object is a step of mixing and stirring 5 to 100 w / v% acrylamide with a promoter and a crosslinking agent to form a first mixed liquid, the first mixed liquid Mixing and stirring a powdered zirconium mesostructure in the mixture to form a second mixture, injecting a reaction initiator into the second mixture, forming a gel, and molding the gel to a predetermined size to form a granular zirconium mesostructure. Characterized in that it comprises a step of forming.

Regeneration method of the granular zirconium meso structure and phosphorus recovery method according to the present invention by reacting the granular zirconium meso structure in which phosphorus is adsorbed using any one or a combination of aqueous solution of sodium hydroxide solution, sodium chloride solution, sodium sulfate solution as a desorption solution It is characterized by desorbing the adsorbed phosphorus.

The apparatus for regenerating and recovering the granular zirconium mesostructure according to the present invention includes a first reaction chamber and a second reaction chamber that are spatially separated by an anion exchange membrane, and the first reaction chamber includes a granular zirconium meso structure in which phosphorus is adsorbed. And a cathode in the first reaction chamber, an anode in the second reaction chamber, an aqueous sodium hydroxide solution circulates in the first reaction chamber, and an aqueous phosphate solution circulates in the second reaction chamber. It features.

In addition, in the regeneration and recovery of phosphorus of the granular zirconium meso structure according to the present invention, the spaces of the first, second and third reaction chambers are sequentially defined by an anion exchange membrane and a cation exchange membrane disposed at a predetermined distance. The first reaction chamber is provided with a granular zirconium meso structure in which phosphorus is adsorbed, the first reaction chamber is provided with a cathode, the third reaction chamber is equipped with an anode, and the aqueous sodium hydroxide solution is circulated in the first reaction chamber, An aqueous solution of phosphoric acid circulates in the second reaction chamber, and an aqueous sulfuric acid solution circulates in the third reaction chamber.

In addition, the regeneration and phosphorus recovery method of the granular zirconium meso structure using the regeneration of the granular zirconium meso structure and the phosphorus recovery device according to the present invention is the granular zirconium meso by the hydroxide ions generated from the cathode and the hydroxide ions separated from sodium hydroxide Phosphorus ions are desorbed from the structure, and the desorbed phosphorus ions pass through the anion exchange membrane and react with the hydrogen ions generated at the anode to form phosphoric acid.

In addition, the regeneration and phosphorus recovery method of the granular zirconium meso structure using the regeneration of the granular zirconium meso structure and the phosphorus recovery device according to the present invention is the granular zirconium meso by the hydroxide ions generated from the cathode and the hydroxide ions separated from sodium hydroxide Phosphorus ions are desorbed from the structure, and the desorbed phosphorus ions pass through the anion exchange membrane and react with hydrogen ions generated at the anode and hydrogen ions separated from sulfuric acid to form phosphoric acid.

Hereinafter, a manufacturing method, a regenerating method, and a phosphorus recovery method of the granular zirconium meso structure according to an embodiment of the present invention will be described in detail with reference to the drawings. 1 is a flowchart illustrating a method of manufacturing a granular zirconium mesostructure according to an embodiment of the present invention.

The method of manufacturing a granular zirconium mesostructure according to an embodiment of the present invention is carried out in the process as shown in FIG.

First, a promoter and a crosslinking agent are mixed in 5 to 100 w / v% acrylamide, and the mixed solution is sufficiently stirred for 1 hour or more (S101). Here, as the accelerator, 3-dimethylaminopropionitrile (3- (dimethylamino) propionitrile) is used at 0.5 to 5.0 w / v%, and as a crosslinker, methylenebisacrylamide (NN'-methylene-bis-acrylamide) is used. ) May be used from 0.5 to 5.0 w / v%. In addition, the acrylamide is preferably 90 w / v%.

Subsequently, 10 to 200 w / v% of the powdered zirconium meso structure is mixed into the solution in which the acrylamide, the accelerator and the crosslinking agent are mixed and stirred (S102). Then, by injecting a reaction initiator (initiator) to form a polymer gel (gel) (S103) (S104). In this case, 5 w / v% of potassium persulfate may be used as the reaction initiator.

Finally, when the gel is formed into a granular zirconium meso structure having a predetermined size, the preparation of the granular zirconium meso structure according to an embodiment of the present invention is completed (S105). Molding of the gel (gel) may use a mold (mold) as shown in Figure 2a, the size of the molded granular zirconium meso structure can be modified and carried out in various ways, but in one embodiment to 1 to 7mm It can manufacture. FIG. 2B is a photograph showing a granular zirconium mesostructure formed by using the mold of FIG. 2A, and FIG. 2C is a cross-sectional view of the granular zirconium mesostructure of FIG. 2B.

On the other hand, the physicochemical and phosphorus removal characteristics of the granular zirconium mesostructures prepared by the above method are as follows.

First, look at the effect of the pH of the granular zirconium mesostructure prepared according to an embodiment of the present invention as follows. Figure 3 is a graph showing the effect of the pH of the granular zirconium mesostructure prepared according to an embodiment of the present invention. In the experiment of FIG. 3, 0.7 g of a granular zirconium mesostructure was reacted with 1000 ppm PO ₄ ^{3 −} at a temperature of 20 ° C. for 24 hours at each pH concentration.

As a result of the experiment, the partition coefficient K _d ( K _d = M _ZM / M _S ) was influenced by the pH of the phosphorus (P) ion reacted with the granular zirconium mesostructure prepared according to the embodiment of the present invention. It was measured to be an independent function of equilibrium concentration. Here, M _ZM and M _S refer to the amount of ion exchanged phosphorus ions per 1 g of the granular zirconium mesostructure and the amount of phosphorus ions remaining per mL of solution, respectively. At pH 12, since the equivalent concentration is 0.01N and the 1000 ppm of phosphorus-containing solution is 0.0035N, the partition coefficient is considered to be reduced because the granular zirconium sulfate compound is replaced with hydroxide ions rather than phosphorus ions due to the concentration difference. Therefore, the granular zirconium mesostructures prepared according to one embodiment of the present invention, unlike metal adsorbents such as iron oxide or aluminum oxide, have been found to be active adsorbents in acidic and alkaline conditions. For reference, in the case of a metal adsorbent which is active only in an acidic condition, an acidic solution should be added in an alkaline condition, which causes additional maintenance costs and is difficult to use on site due to the expansion of additional facilities. In the case of the invention, it is possible to use the entire pH range depending on the dosage of the meso structure.

Next, with reference to Figure 4 and Table 1 will be examined the adsorption characteristics according to the content of the powder zirconium meso structure to be immobilized in acrylamide. Figure 4 shows a pseudo-second-order equation according to the content of the powder zirconium mesostructures immobilized on acrylamide, Table 1 shows the adsorption capacity and rate constant according to the content of the powder zirconium mesostructures immobilized on acrylamide. The experimental conditions of FIG. 4 and Table 1 are 0.7g of granular zirconium mesostructures having a powdered zirconium mesostructure content of 40 to 100 w / v% at a temperature of 20 ° C. and 1000 ppm of a phosphorus containing solution.

Kinetic test results for the phosphorus of granular zirconium mesostructures (ZM) were reported by Ho and Mackay (YS Ho and G. McKay, The kinetics of sorption of divalent metal ions onto sphagnum moss peat, Water Research, Volume 34, Issue) 3, 2000, Pages 735-742.) Were analyzed using the quasi-secondary reaction model, and 50 ml of 1000 ppm phosphate was placed in a 60 ml glass tube, and a certain amount of granular zirconium mesostructure prepared therein was added to a rotary shaker ( rotary shaker, 099ARD4512, Glass col co., USA), take a certain amount of solution at timed intervals, filter with 0.45μm membrane filter, and measure the residual phosphorus concentration in the solution (ion chromatograpy, DX-120, DIONEX). , USA). A pseudo-second order kinetic model is shown in Equation 1 below.

Where q _t is the amount of phosphorus adsorbed at time t (mg / g), q _e is the amount of phosphorus adsorbed when equilibrium is reached, k is the pseudo-second order reaction rate constant, g / mg Min))

Table 1 Adsorption capacity and rate constant according to the content of powder zirconium mesostructure (ZM) immobilized on acrylamide

k [g / mg min] qe [mg / g] r2 40% ZM 2.01 × 10-4 54.90 0.99 60% ZM 2.20 × 10-4 61.97 0.99 80% ZM 3.04 × 10-4 63.94 0.99 100% ZM 4.05 × 10-4 70.46 0.99

In the experiments of FIG. 4 and Table 1, it was observed that the polymer gel is not formed in the case of more than 100 w / v%, it is because the lack of the acrylamide content that provides mechanical properties. On the other hand, as the content of powder zirconium mesostructures increased, the adsorption capacity for the adsorption of phosphorus ions increased and the adsorption rate also increased relatively. When the content of the powdered zirconium mesostructure is 100 w / v%, the adsorption capacity of the granular acrylamide is 70.46 mg / g and corresponds to 2.23 meq / g. In addition, the rate constant of the granular zirconium meso structure immobilized with acrylamide was measured to be 4.05 × 10 −4 g / mg · min.

Next, the adsorption capacity and the rate constant according to the size of the granular zirconium mesostructure will be described with reference to Table 2. The experiment of Table 2 was carried out under the condition of reacting granular zirconium mesostructures of 1, 3 and 7 mm size to 1000 ppm of phosphorus-containing solution under a temperature of 20 ° C. In addition, the input content of the granular zirconium meso structure is 0.7g.

<Table 2> Adsorption capacity and rate constant according to the size of granular zirconium mesostructure

Size (cm) Meso Structure k [g / mg min] qe [mg / g] r2   7 40% ZM 2.01 × 10-4 54.90 0.99 60% ZM 2.20 × 10-4 61.97 0.99 80% ZM 3.04 × 10-4 63.94 0.99 100% ZM 4.05 × 10-4 70.46 0.99 3 100% ZM 6.04 × 10-4 69.72 0.99 One 100% ZM 7.07 × 10-4 69.63 0.99

To investigate the effect of surface area on the adsorption capacity, the adsorption rate constant and adsorption capacity were measured using pseudo-second order equations. In general, the smaller the particles, the greater the frequency of reaction with phosphorus ions in the aqueous solution, and the adsorption capacity and rate constant would be relatively higher than those of the larger particles. As shown in Table 2, the rate constant showed a higher value as the particle size was smaller and a faster reaction rate as the specific surface area was increased, but it did not show a significant difference in adsorption capacity.

Next, the FE-SEM was analyzed to observe the particle surface according to the content of the powder zirconium mesostructures immobilized in acrylamide. The FE-SEM (FEI XL-30 FEG ESEM with EDS) photograph observed at 5000 times is shown in FIG. 5, in which the white part is a powder zirconium mesostructure and the gray part is acrylamide. Figure 5 shows the composition analysis results through the FE-SEM photographs and EDS showing the particle surface of the granular zirconium mesostructures according to the content of the powder zirconium mesostructures immobilized on acrylamide. In Figure 5, the right part is the result of the composition analysis through the EDS.

As shown in FIG. 5, it was observed that the white portion increased as the powder zirconium mesostructure content increased. This qualitative analysis was able to quantitatively observe that the zirconium was immobilized in acrylamide through the compositional analysis of the nano-region using EDS, and the Zr peak became larger as the content of the powdered zirconium mesostructure was increased. .

Also, as shown in FIG. 6, the pore size of acrylamide polymer gel is less than 200 nm (Estimation of polyacrylamide-gel pore-size from ferguson plots of normal and anomalously migrating dna fragments, .I. Gels containing 3-percent n Particle size analysis (Particle size distribution, CILAS 1064 Liquid, range 0.04 to 500.00 μm) of the zirconium powders prepared, considering n'-methylenebisacrylamide, Holmes DL, Stellwagen NC, Electrophoresis 1991, 12, pp253-263), 10% The diameter at was 7.07 μm, the diameter at 50% was 49.14 μm, the diameter at 90% was 104.73 μm and the mean diameter was 53.33 μm. Thus, it has been demonstrated that complete entrapment of zirconium mesostructure powders immobilized in acrylamide is achieved.

Next, the transmission coefficient was measured to measure the hydraulic resistance of the granular zirconium mesostructures. In general, the permeation coefficient acts as an important factor in the scale-up of the reactor. If the permeation coefficient is low, the operating pressure increases as the scale of the reactor increases, making it difficult to use in the field. Therefore, in this embodiment, the permeation coefficient was compared with that of the commercial ion exchange resin. Table 3 shows the transmission coefficient according to the particle size of the granular zirconium meso structure.

<Table 3> Permeation Coefficients of Particle Size of Granular Zirconium Meso Structures

media diameter (mm) Permeability (l / m.hr.MPa)  Commercial Anion Exchange Resin (Amberlite IRA 402Cl, Rohn & Haas Co.)   0.7   49,930  Granular Zirconium Meso Structure (ZM_Acrylamide) 1.0 71,520 3.0 97,480 7.0 175,000

As shown in Table 3, the permeation coefficient of the granular zirconium mesostructures increased with increasing particle size and showed similar values compared to commercial anion exchange resins.

Above, the physicochemical and phosphorus removal characteristics of the granular zirconium meso structure and the prepared granular zirconium meso structure according to an embodiment of the present invention have been described. Hereinafter, the regeneration method of the granular zirconium meso structure and the phosphorus recovery method according to an embodiment of the present invention will be described. 7 is a flowchart illustrating a regeneration method and a phosphorus recovery method of the granular zirconium meso structure according to the first embodiment of the present invention.

The first embodiment of the present invention uses a physicochemical method. First, as shown in FIG. 7, a process of removing phosphorus by a granular zirconium meso structure is performed. That is, the inlet containing phosphorus is supplied to the reactor while the granular zirconium mesostructure is filled in the reactor so that the phosphorus in the influent is adsorbed onto the granular zirconium mesostructure. Here, the granular zirconium meso structure is a granular zirconium meso structure prepared by FIG. 1, that is, using acrylamide.

In such a state, the desorption solution is used to desorb the phosphorus adsorbed onto the granular zirconium meso structure. At this time, the desorption solution may be used in the sodium chloride solution, sodium hydroxide solution or sodium sulfate solution of 0.05 ~ 1.0N or a combination thereof. In addition, regeneration of the granular zirconium mesostructure is achieved due to the desorption of phosphorus. In other words, the desorption and regeneration process is performed at the same time.

On the other hand, through the desorption process of the adsorbed phosphorus, the desorption solution and the phosphorus desorbed from the granular zirconium meso structure is discharged included in the desorption solution consumed in the desorption process, such a desorption solution is consumed through Phosphorus can be selectively removed.

Specifically, first, sodium hydroxide is added to the spent desorption solution to increase the pH concentration of the desorbed solution. Then, when the consumed desorption solution is reacted with calcium chloride, calcium phosphate can be recovered, and the recovered calcium phosphate can be used as a fertilizer. In addition, the desorption solution from which the calcium phosphate is removed means the regenerated solution of the original desorption solution. Accordingly, the regenerated desorption solution can be reused in the desorption process.

A second embodiment of the present invention utilizes an electrochemical method, which requires a mechanical device as shown in FIGS. 8A and 8B to implement the electrochemical method. 8A and 8B are detailed embodiments for implementing the second embodiment of the present invention. First, the mechanical configuration of FIG. 8A and the method of regenerating electrochemical granular zirconium mesostructures using the same and a method of recovering phosphorus will be described. Let's do it.

As shown in FIG. 8A, an apparatus for implementing a method for regenerating an electrochemical granular zirconium mesostructure and a method for recovering phosphorus includes a first reaction chamber 110 and a second reaction chamber 120 and the first reaction chamber. The 110 and the second reaction chamber 120 are spatially separated by an anion exchange membrane (AEM). In addition, a cathode (−) is provided in the first reaction chamber 110 and an anode (+) is provided in the second reaction chamber 120, and a granular zirconium meso structure in which phosphorus is adsorbed in the first reaction chamber 110 is provided. Is filled. Here, the granular zirconium meso structure is a granular zirconium meso structure manufactured by the process of FIG.

In the apparatus having the above configuration, the regeneration method of the electrochemical granular zirconium meso structure and the recovery method of phosphorus proceed as follows.

First, in a state in which granular zirconium meso structure in which phosphorus is adsorbed is filled in the first reaction chamber 110, an aqueous sodium hydroxide solution is added to the first reaction chamber 110, and an aqueous phosphoric acid solution is added to the second reaction chamber 120. Let's do it. The aqueous sodium hydroxide solution and the phosphoric acid solution introduced into the first and second reaction chambers 110 and 120 are discharged through the discharge ports provided in the first and second reaction chambers 110 and 120, respectively. Circulates the reaction chamber. At this time, the concentration of the aqueous sodium hydroxide solution circulating in the first reaction chamber 110 is preferably 0.1 to 0.5M, the concentration of the aqueous phosphoric acid solution circulating in the second reaction chamber 120 is 0.01 to 0.1M is appropriate. Do.

In this state, electric power is applied to the cathode and the anode to generate an electric field in the first and second reaction chambers 110 and 120. Accordingly, hydroxide ions (OH ⁻ ) are generated at the cathode, and hydrogen ions (H ⁺ ) are generated at the anode, and the first and second reaction chambers 110 and 120 are each pH 11-12. It is maintained at a concentration of pH 3-4.

On the other hand, the hydroxide ion (OH ^-) generated from the anode and hydroxide ions (OH ^-) separated from sodium hydroxide (NaOH) is desorbed and the desorbed ions (PO ₄ ^3-), which is adsorbed on the granular zirconium meso structure Phosphorus ions pass through the anion exchange membrane to the second reaction chamber 120. Phosphorous ions (PO ₄ ^3- ) transferred to the second reaction chamber 120 are combined with hydrogen ions (H ⁺ ) generated at the anode to generate phosphoric acid (H ₃ PO ₄ ). The generated phosphoric acid is mixed with the aqueous phosphoric acid solution circulating in the second reaction chamber 120 and discharged to the outside.

Phosphorus adsorbed on the granular zirconium mesostructure is removed through the above process, thereby regenerating the granular zirconium mesostructure, thereby effectively recovering the desorbed phosphorus by converting the desorbed phosphorus into phosphoric acid.

Next, the mechanical configuration of FIG. 8B and the regeneration method of the electrochemical granular zirconium meso structure using the same and the recovery method of phosphorus will be described.

As shown in FIG. 8B, an apparatus for implementing a method for regenerating an electrochemical granular zirconium meso structure and a method for recovering phosphorus includes an anion exchange membrane (AEM) and a cation exchange membrane (CEM) disposed at a predetermined distance. do. The space of the first, second and third reaction chambers 210, 220, 230 is defined by the anion exchange membrane and the cation exchange membrane. Specifically, the left side of the anion exchange membrane is defined as the first reaction chamber 210, the second reaction chamber 220 between the anion exchange membrane and the cation exchange membrane, and the right side of the cation exchange membrane is defined as the third reaction chamber 230. The first reaction chamber 210 is provided with a cathode (−), and the third reaction chamber 230 is provided with an anode (+), and the first reaction chamber 210 is filled with a granular zirconium meso structure in which phosphorus is adsorbed. do. Here, the granular zirconium meso structure is a granular zirconium meso structure manufactured by the manufacturing method of FIG. 1, that is, acrylamide.

In the apparatus having the above configuration, the regeneration method of the electrochemical granular zirconium meso structure and the recovery method of phosphorus proceed as follows.

First, in a state in which a granular zirconium meso structure in which phosphorus is adsorbed is filled in the first reaction chamber 210, an aqueous sodium hydroxide solution is used in the first reaction chamber 210, and an aqueous phosphoric acid solution is used in the second reaction chamber 220. 3 Aqueous sulfuric acid is added to the reaction chamber 230. The sodium hydroxide solution, the phosphoric acid solution and the sulfuric acid solution introduced into the first, second and third reaction chambers 210, 220 and 230 are discharged through the outlets provided in the first, second and third reaction chambers. The aqueous solutions circulate through the respective reaction chambers. At this time, the concentration of the aqueous sodium hydroxide solution circulating in the first reaction chamber 210 is preferably 0.1 to 0.5M, the concentration of the aqueous phosphoric acid solution circulating in the second reaction chamber 220 is preferably 0.01 to 0.1M. The concentration of the aqueous sulfuric acid solution circulating in the third reaction chamber 230 is preferably 0.01 to 0.1M.

In this state, electric power is applied to the cathode and anode to generate electric fields in the first and third reaction chambers 210 and 230. Accordingly, hydroxide ions (OH ⁻ ) are generated at the cathode and hydrogen ions (H ⁺ ) are generated at the anode, and the first and third reaction chambers are maintained at pH 11-12 and pH 3-4, respectively. do.

On the other hand, the hydroxide ion (OH ^-) generated from the anode and hydroxide ions (OH ^-) separated from sodium hydroxide (NaOH) is desorbed and the desorbed ions (PO ₄ ^3-), which is adsorbed on the granular zirconium meso structure Phosphorus ions pass through the anion exchange membrane to the second reaction chamber 220. Phosphorus ions (PO ₄ ^3- ) transferred to the second reaction chamber combine with hydrogen ions (H ⁺ ) generated from the anode and hydrogen ions (H ⁺ ) separated from sulfuric acid (H ₂ SO ₄ ) to phosphoric acid (H ₃ PO ₄ ) is generated. The generated phosphoric acid is mixed with the aqueous phosphoric acid solution circulating in the second reaction chamber 220 and discharged to the outside. Here, to be produced by the hydrogen ion (H ⁺⁾ and sulfuric acid (H ₂ SO ₄₎ The proton separated at (H ⁺⁾ the third reaction chamber 230 is generated at the anode pass through the cation exchange membrane movement chamber the second reaction It is.

In the above, the regeneration method of the electrochemical granular zirconium meso structure and the recovery method of phosphorus using the apparatus of FIG. 8B have been described. Compared to the method of FIG. 8A, sulfuric acid is used as a source of hydrogen ions in addition to the hydrogen ions (H ⁺ ) generated at the anode. In addition, it is possible to minimize the unreacted phosphorus ions in the second reaction chamber, thereby improving the recovery efficiency of phosphorus.

On the other hand, the applicant has implemented the technical principle of Figure 8b with a real device. 9 is an apparatus for regenerating and recovering phosphorus in an electrochemical granular zirconium mesostructure according to an embodiment of the present invention. 9 briefly shows a plate packing for fixing the module, a plated platinum plated anode in titanium, a cathode made of SUS316 material, an anode and cathode chamber, each of which is provided with the anode and the cathode, and a flow path. It consists of a distributor, a gasket and the like for forming.

In the above, the regeneration method of the physicochemical and electrochemical granular zirconium mesostructures and the recovery method of phosphorus according to the first and second embodiments of the present invention have been described. The adsorption capacity and rate constant after physicochemical or electrochemical regeneration of the granular zirconium mesostructure are shown in Table 4.

<Table 4> Adsorption capacity and rate constant of physicochemical / electrochemical regeneration of granular zirconium mesostructures

As shown in Table 4, the comparison of adsorption capacity and rate constant after physicochemical / electrochemical regeneration of the granular zirconium mesostructure showed 96.68∼99.91% regeneration efficiency. When electrochemical regeneration was performed, the power consumption was measured to be 1.12 kWh / ton, and it was confirmed that regeneration of granular material was possible with very low power. This high regeneration efficiency enables the repeated use of the granular zirconium mesostructures, thereby reducing the maintenance costs when in practice, thereby improving the economics of the process.

A method for producing a granular zirconium meso structure according to the present invention, and an apparatus and method for regenerating and recovering phosphorus of a granular zirconium meso structure are as follows.

Powdered zirconium mesostructures have a high specific surface area, high surface reaction and adsorption capacity, and despite the advantages of effective removal of phosphate in water, they are not easy to handle due to the powder form, but also have high operating pressure and high suspended solids. On-site use has been difficult until now because the included influent was not available.

In order to overcome the above problems, the convenience of in situ was improved by immobilizing the powder zirconium mesostructure in acrylamide, and a method of regenerating and reusing the used granular zirconium mesostructure was physically and chemically suggested. Phosphorus ions released by regeneration were presented as a method of using calcium phosphate as a fertilizer and a phosphate solution to provide a resource recycling technology for phosphate ore that will be depleted in the next 100 years.

In the future, the effluent water quality standards of environmental foundations will be strengthened further, and the adsorption technology using the granular zirconium meso structure can maximize the treatment efficiency and improve the economic efficiency by recycling the phosphorus ions contained in the pollutants. It works.

Claims (17)

Mixing 5 to 100 w / v% acrylamide with a promoter for increasing the gelation reaction rate of acrylamide and a crosslinking agent which connects acrylamide to form a net structure to form a first mixed solution; Mixing and stirring a powder zirconium mesostructure in the first mixture to form a second mixture; Injecting a reaction initiator which initiates the transfer of acrylamide to the gel in the second mixed solution to form a gel; And And forming a granular zirconium mesostructure by molding the gel to a predetermined size. The method of claim 1, wherein the accelerator is 3-dimethylaminopropionitrile. The method of claim 1, wherein the content of 3-dimethylaminopropionitrile is 0.5 to 5.0 w / v%. The method of claim 1, wherein the crosslinking agent is methylene bis acrylamide (NN'-methylene-bis-acrylamide). The method of claim 4, wherein the content of the crosslinking agent is 0.5 to 5.0 w / v%. The method of claim 1, wherein the content of the powder zirconium mesostructure is 10 to 200 w / v%. The method of claim 1, wherein the content of acrylamide is 90 w / v%. In the reclaiming method of granular zirconium mesostructures produced by the method for producing granular zirconium mesostructures of claim 1 and the method of recovering phosphorus, Regeneration of the granular zirconium meso structure, characterized in that the adsorbed phosphorus is desorbed by reacting the granular zirconium meso structure in which phosphorus is adsorbed using an aqueous solution of sodium hydroxide solution, sodium chloride solution or sodium sulfate solution or a combination thereof. Method and recovery of phosphorus. The method of claim 8, further comprising the step of recovering calcium phosphate by injecting sodium hydroxide into the desorption solution used in the desorption process of the granular zirconium meso structure adsorbed by phosphorus, and then reacting the desorption solution with calcium chloride. A method for regenerating granular zirconium mesostructures and a method for recovering phosphorus. 9. The method of claim 8, wherein the concentration of any one of the aqueous sodium hydroxide solution, aqueous sodium chloride solution, and aqueous sodium sulfate solution or a combination thereof is 0.05 to 1.0 N. In the regeneration and phosphorus recovery apparatus of the granular zirconium meso structure manufactured according to claim 1, A first reaction chamber and a second reaction chamber are spatially separated by an anion exchange membrane, and the first reaction chamber is provided with a granular zirconium meso structure in which phosphorus is adsorbed, and the first reaction chamber has a negative electrode, and the second reaction chamber. The reaction chamber is provided with an anode, An aqueous sodium hydroxide solution circulates in the first reaction chamber, and an aqueous phosphoric acid solution circulates in the second reaction chamber, wherein the granular zirconium meso structure is recovered. In the regeneration and phosphorus recovery apparatus of the granular zirconium meso structure manufactured according to claim 1, Spaces of the first, second and third reaction chambers are sequentially defined by anion exchange membranes and cation exchange membranes spaced at a predetermined distance, and the first reaction chamber is provided with a granular zirconium meso structure in which phosphorus is adsorbed. A cathode is provided in the first reaction chamber, and an anode is provided in the third reaction chamber. Regeneration of the granular zirconium mesostructure, wherein an aqueous sodium hydroxide solution circulates in the first reaction chamber, an aqueous phosphoric acid solution circulates in the second reaction chamber, and an aqueous sulfuric acid solution circulates in the third reaction chamber. Recovery device of phosphorus. 13. The apparatus for regenerating and recovering phosphorus zirconium mesostructures according to claim 11 or 12, wherein the concentration of the aqueous sodium hydroxide solution is 0.1 to 0.5 M. 13. The apparatus for regenerating and recovering phosphorus zirconium mesostructures according to claim 11 or 12, wherein the concentration of the aqueous solution of phosphoric acid is 0.01 to 0.1 M. 13. The apparatus for regenerating and recovering phosphorus zirconium mesostructures according to claim 12, wherein the concentration of the sulfuric acid aqueous solution is 0.01 to 0.1 M. In the method of regenerating and recovering the granular zirconium meso structure using the reclaiming granular zirconium meso structure of claim 11 and the recovery of phosphorus, Phosphorus ions are desorbed from the granular zirconium mesostructure by the hydroxide ions generated at the cathode and the hydroxide ions separated from sodium hydroxide, and the desorbed phosphorus ions pass through the anion exchange membrane and react with the hydrogen ions generated at the anode. Regenerating granular zirconium mesostructures and phosphorus recovery method characterized by forming a phosphoric acid. In the method of regenerating the granular zirconium meso structure and the recovery of phosphorus using the regeneration of the granular zirconium meso structure of claim 12 and the recovery of phosphorus, Phosphorus ions are desorbed from the granular zirconium mesostructure by the hydroxide ions generated at the cathode and the hydroxide ions separated from the sodium hydroxide, and the desorbed phosphorus ions pass through the anion exchange membrane and then generate hydrogen ions and sulfuric acid at the anode. A method of regenerating and recovering the granular zirconium mesostructure, characterized by reacting with hydrogen ions separated from to form phosphoric acid.

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