Deep phosphorus removal material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of water treatment, in particular to a deep phosphorus removal material and a preparation method and application thereof.The preparation method at least comprises the following steps that S1, lanthanide series metal salt and bentonite are dissolved in an ethanol solution to be subjected to ultrasonic treatment, and then a lanthanide series metal salt alcoholic solution and a bentonite alcoholic solution are obtained; s2, sequentially adding the lanthanide metal salt alcoholic solution and the organosilane ammonia hydrolysate into a magnetically dispersed bentonite alcoholic solution sample, dipping for 6 hours at normal temperature, and filtering to obtain a solid precipitate; and S3, sequentially washing, drying, grinding and sieving the solid precipitate to obtain the deep phosphorus removal material. According to the deep phosphorus removal material provided by the invention, the adsorption capacity and the adsorption rate are improved, and the removal rate of phosphorus can still be maintained at 71.1% or above after five times of adsorption-desorption cycles (the single cycle time is 450 minutes) are continuously carried out; meanwhile, excellent tolerance is shown in a complex water body, good potential of selectively adsorbing phosphorus is shown, and good market application prospects are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of water treatment, and particularly relates to a deep phosphorus removal material, a preparation method thereof, and an application thereof. Background Art

[0002] Traditional biological treatment technologies have limitations in removing phosphate from sewage. The phosphate concentration in their effluent is usually higher than 0.5 mg / L, which will lead to excessive phosphorus (P) being discharged into natural water bodies. This may cause eutrophication phenomena such as algal blooms and red tides, and thus pose a serious threat to the drinking water supply and the biodiversity of aquatic ecosystems. As an efficient and economical water treatment technology, the adsorption method has been widely used in the field of phosphorus removal to meet the effluent requirements for deep phosphorus removal, that is, the phosphate concentration in the effluent is reduced by one order of magnitude compared with traditional technologies.

[0003] At present, a series of high-capacity metal-based adsorption materials have been developed for the removal of phosphorus in water bodies. However, most of these materials have the risk of metal toxicity, which may pose a potential hazard to the water ecosystem, and have a narrow application range, making it difficult to adapt to complex and changeable water environments. The synthesis process is complex, resulting in high production costs and being not conducive to large-scale industrial applications. In contrast, bentonite-based materials have attracted much attention due to their natural non-toxic properties and good economic benefits. However, the existing bentonite-based materials have low adsorption rates and adsorption capacities for phosphate in water bodies in actual applications, making it difficult to meet the requirements for efficient phosphorus removal.

[0004] So far, many metal-modified bentonite materials (such as iron-modified, lanthanum-modified, and zirconium-modified bentonites, etc.) have been developed to meet strict phosphorus discharge standards. Among them, lanthanum has been widely used in bentonite modification due to its stronger affinity for phosphate and the stability of the product lanthanum phosphate. Its commercial product lanthanum-modified bentonite (LMB) is very popular in the eutrophication management applications of 200 lakes around the world. However, commercial lanthanum-modified bentonite shows a slow adsorption rate and poor adsorption selectivity in low-concentration phosphorus water bodies, making it difficult to achieve the goal of deep phosphorus removal (lower than 0.1 mg / L). In addition, coexisting anions and organic matter in actual water bodies will significantly interfere with the phosphorus removal effect of commercial lanthanum-modified bentonite, reducing its adsorption performance. The above factors severely limit the popularization of existing lanthanum-modified bentonite-based materials in industrial and market applications. Therefore, developing a new type of bentonite material with high adsorption performance, anti-interference ability, environmental friendliness, and economic applicability has important scientific significance and application value. Summary of the Invention

[0005] In order to solve the above problems, the first aspect of the present invention provides a preparation method of a deep phosphorus removal material, which at least includes the following steps: S1. Dissolve the lanthanide metal salt and bentonite in ethanol solution respectively, and obtain the lanthanide metal salt ethanol solution and bentonite ethanol solution after ultrasonic treatment. S2. Sequentially add the lanthanide metal salt ethanol solution and the organosilane ammonia hydrolysis solution to the magnetically dispersed bentonite ethanol solution sample, impregnate at room temperature for 6 h, and then filter to obtain a solid precipitate. S3. Wash, dry, grind and sieve the solid precipitate to obtain a deep phosphorus removal material.

[0006] In one embodiment, the dosage ratio of the lanthanide metal salt to the ethanol solution in step S1 is 0.1307 g: 20 mL.

[0007] In one embodiment, the dosage ratio of the bentonite to the ethanol solution in step S1 is 1 g: 20 mL.

[0008] In one embodiment, the conditions of the ultrasonic treatment in step S1 are: the ultrasonic frequency is 53 kHz, and the ultrasonic time is 10 - 20 min. Preferably, the ultrasonic time is 10 min.

[0009] In one embodiment, after the bentonite is dissolved in the ethanol solution and ultrasonically treated in step S1, it also needs to be subjected to high-speed dispersion treatment. The conditions of the high-speed dispersion treatment are 1000 rpm at room temperature, and the dispersion time is 20 - 30 min. Preferably, the dispersion time is 25 min.

[0010] In one embodiment, the mass concentration of the ethanol solution is 50%.

[0011] In one embodiment, the preparation method of the organosilane ammonia hydrolysis solution is: dissolve the organosilane ammonia in deionized water, and the hydrolysis time is 10 - 20 min. Preferably, the hydrolysis time is 10 min.

[0012] In one embodiment, the mass concentration of the organosilane ammonia in the organosilane ammonia hydrolysis solution is any one of 1.3%, 2.6%, 5.2% and 10.4%.

[0013] In one embodiment, the conditions of the magnetic dispersion in step S2 are magnetic stirring at room temperature, and the rotation speed is 200 rpm.

[0014] In one embodiment, the lanthanide metal salt includes lanthanum chloride.

[0015] In one embodiment, the organosilane ammonia includes 3-(phenylamino)propyltrimethoxysilane.

[0016] In one embodiment, the specific steps of S3 are as follows: The solid precipitate is rinsed successively with water and ethanol, dried at room temperature with ventilation for 12 h, ground, and sieved through a 200-mesh sieve to obtain the deep phosphorus removal material.

[0017] The second aspect of the present invention provides a deep phosphorus removal material prepared according to the above preparation method.

[0018] In one embodiment, the deep phosphorus removal material is NH2-La-Ben(Et).

[0019] The third aspect of the present invention provides an application of the deep phosphorus removal material for removing phosphate in water bodies.

[0020] Beneficial effects

[0021] 1. The present invention innovatively develops a room-temperature aqueous phase co-assembly modification process for bentonite, and constructs a bifunctional active interface through the synergistic coordination of 3-(phenylamino)propyltrimethoxysilane (APTES) and lanthanum chloride. The molecular-level interface engineering promotes the protonation reconstruction of amino groups on the surface of silicate, significantly improves the mass transfer efficiency on the surface of silicate, realizes efficient adsorption at a low phosphorus concentration of 0.5 mg / L, and significantly enhances the adsorption kinetic rate and adsorption selectivity.

[0022] 2. The deep phosphorus removal material prepared in this application has improved adsorption capacity (58.8 mg / g) and adsorption rate (0.82 g / (mg•min)), and after continuously performing 5 adsorption-desorption cycles (single cycle time of 450 minutes), the phosphorus removal rate can still be maintained above 71.1%.

[0023] 3. The present invention uses an alcohol-based dispersion system to promote the highly uniform load distribution of lanthanide metals on the surface of the bentonite carrier. By increasing the exposure density and spatial accessibility of active sites, the interfacial contact probability with phosphate ions is significantly improved. This structural feature promotes the directional coordination of the inner Helmholtz layer at the adsorption interface and strengthens the specific inner-sphere complexation mechanism, thus achieving double-effect enhancement in a complex water environment: maintaining strong electrostatic trapping ability and excellent anti-interference ability. Based on this synergistic mechanism, the material still maintains 97.2% of the phosphorus adsorption capacity under an ultra-high hydraulic shock load of 8000 BV, and its high-efficiency mass transfer characteristics and selective adsorption advantages provide an innovative solution for the efficient adsorption of low-concentration phosphorus.

[0024] 4. The preparation method provided in this application is simple, and the preparation raw materials are easy to obtain and inexpensive. Using a simple impregnation method, it has significant economic benefits compared with metal-based materials and bentonite matrix materials. Description of the drawings

[0025] Figure 1Comparison chart of phosphorus removal efficiency of the deep phosphorus removal materials prepared in Examples 1-4; Figure 2 Isothermal curve diagram of phosphate adsorption by the deep phosphorus removal materials prepared in Example 3 and Comparative Examples 1-2; Figure 3 Kinetic curve diagram of phosphate adsorption by the deep phosphorus removal materials prepared in Example 3 and Comparative Examples 1-2; Figure 4 Cyclic adsorption performance diagram of the deep phosphorus removal material prepared in Example 3;

[0026] Figure 5 Comparison chart of La ion leaching in the cyclic adsorption experiment of phosphate by the deep phosphorus removal materials prepared in Example 3 and Comparative Examples 1-2; Figure 6 Comparison chart of phosphorus concentration in the filtrate after treating phosphate by the deep phosphorus removal materials prepared in Example 3 and Comparative Examples 1-2 in the fixed-bed adsorption column; Figure 7 Distribution coefficient diagram of different coexisting ions by the deep phosphorus removal materials prepared in Example 3 and Comparative Examples 1-2; Figure 8 For the deep phosphorus removal materials prepared in Example 3 and Comparative Examples 1-2 for different coexisting ions (NO3 - , SO4 2- ) relative separation constant diagram; Figure 9 For the deep phosphorus removal materials prepared in Example 3 and Comparative Examples 1-2 for different coexisting ions (Cl – , HCO3 – ) relative separation constant diagram; Figure 10 Phosphorus removal efficiency diagram of the deep phosphorus removal material prepared in Example 3 under different coexisting ion concentrations. Detailed implementation mode

[0027] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. The experimental methods without specific conditions noted in the embodiments are carried out according to conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments without the manufacturer noted are all conventional products that can be obtained through commercial purchase.

[0028] Normal temperature in this application is 24°C.

[0029] Example 1

[0030] In the first aspect of this embodiment, a preparation method of a deep phosphorus removal material is provided, including the following steps: S1. Dissolve 0.1307 g of lanthanum chloride and 0.1 g of bentonite in 20 mL of ethanol solution respectively, and after ultrasonic treatment, obtain lanthanum chloride ethanol solution and bentonite ethanol solution; S2. Sequentially add the lanthanum chloride ethanol solution and the organosilane ammonia hydrolysis solution to the magnetically dispersed bentonite ethanol solution sample, impregnate at room temperature for 6 h, and then filter to obtain a solid precipitate; S3. Wash the solid precipitate with water and ethanol in sequence, conduct ventilation and drying at room temperature for 12 h, then grind it, and pass through a 200-mesh sieve to obtain the deep phosphorus removal material.

[0031] The conditions of ultrasonic treatment in step S1: the ultrasonic frequency is 53 kHz, and the ultrasonic time is 10 min.

[0032] In step S1, after ultrasonic treatment of bentonite dissolved in ethanol solution, high-speed dispersion treatment is also required. The conditions of the high-speed dispersion treatment are 1000 rpm at room temperature, and the dispersion time is 25 min.

[0033] The mass concentration of the ethanol solution is 50%.

[0034] The preparation method of the organosilane ammonia hydrolysis solution is: dissolve organosilane ammonia in deionized water, and the hydrolysis time is 10 min.

[0035] The mass concentration of organosilane ammonia in the organosilane ammonia hydrolysis solution is 1.3%.

[0036] The organosilane ammonia is 3-(phenylamino)propyltrimethoxysilane.

[0037] The conditions of magnetic dispersion in step S2 are magnetic stirring at room temperature, and the rotation speed is 200 rpm.

[0038] In the second aspect of this embodiment, a deep phosphorus removal material prepared according to the above preparation method is provided. The deep phosphorus removal material is denoted as NH2-La-Ben(Et).

[0039] In the third aspect of this embodiment, an application of the deep phosphorus removal material is provided, which is applied to the removal of phosphate in water bodies.

[0040] Example 2

[0041] The specific implementation mode of this example is the same as that of Example 1, the difference is that the mass concentration of organosilane ammonia in the organosilane ammonia hydrolysis solution is 2.6%.

[0042] Example 3 The specific implementation mode of this example is the same as that of Example 1, the difference is that the mass concentration of organosilane ammonia in the organosilane ammonia hydrolysis solution is 5.2%.

[0043] Figure 4 Cyclic adsorption performance diagram of the deep phosphorus removal material prepared in Example 3

[0044] Figure 10 Phosphorus removal efficiency diagram of the deep phosphorus removal material prepared in Example 3 under different coexisting ion concentrations

[0045] Example 4

[0046] The specific implementation manner of this example is the same as that of Example 1, the difference is that the mass concentration of organosilane ammonia in the organosilane ammonia hydrolysis solution is 10.4%.

[0047] Figure 1 Phosphorus removal efficiency comparison diagram of the deep phosphorus removal materials prepared in Examples 1-4

[0048] Comparative Example 1

[0049] The specific implementation manner of this comparative example is the same as that of Example 1, the difference is that the organosilane ammonia hydrolysis solution is not added in the S2 step.

[0050] Comparative Example 2

[0051] This comparative example uses commercially available Phoslock ® phosphorus locking agent, purchased from Shanghai Fengsile Environmental Technology Co., Ltd.

[0052] Performance test

[0053] 1. Phosphorus removal experiment in low-phosphorus-concentration water body Add 100 mg of the deep phosphorus removal materials prepared in Examples 1-4 to a solution with a pH of 7.0 ± 0.5 and an initial phosphorus concentration of 0.5 mg / L, and conduct the phosphorus removal experiments of Examples 1, 2, 3, and 4 respectively. The obtained phosphorus removal efficiencies are shown in the appendix Figure 1 ; From Figure 1 it can be seen that when the APTES concentration increases from 1.3% to 5.2%, the phosphorus removal efficiency of the system shows a linear increasing trend, increasing significantly from 72.9% to 91.5%; while when the APTES concentration exceeds 5.2%, the phosphorus removal efficiency enters a plateau period, and the performance fluctuation range narrows to within ±1.5%.

[0054] 2. Adsorption isotherm and kinetic experiments In the adsorption isotherm experiment, 100 mg of adsorbent (the deep phosphorus removal material of Example 3 and Comparative Examples 1-2) was added to solutions with a pH of 7.0 ± 0.5 and an initial phosphorus concentration of 0.1-200 mg / L. Under the constant temperature condition of 25°C, it was oscillated at a speed of 350 rpm for 12 hours; in the adsorption kinetics experiment, 100 mg of adsorbent was dispersed in 50 mL of a phosphate solution with a concentration of 0.5 mg / L, and the experiment was carried out at 25°C. Within 1-120 minutes, 0.5 mL of water sample was taken at regular intervals to measure the remaining phosphorus concentration. After the oscillation ended, it was filtered using a 0.22 μm polyethersulfone membrane, and the supernatant was collected.

[0055] The test results are shown in Figures 2 - 3 . Through the comparison of the experimental data of the adsorption isotherm ( Figure 2 ) and kinetics ( Figure 3 ), the adsorption capacity and kinetic parameter differences of Example 3, Comparative Example 1 and Comparative Example 2 at different initial phosphorus concentrations were quantitatively revealed. The fitting results of the Langmuir isotherm model showed that at 298K, the maximum adsorption capacity of Example 3 reached 58.8 mg / g, which was 3.36 times and 5.94 times that of Comparative Example 1 (17.5 mg / g) and Comparative Example 2 (9.9 mg / g), respectively. It should be noted that within the range of 0.1-200 mg / L of the initial phosphorus concentration, the adsorption amount-concentration curve of Example 3 showed the steepest upward trend. Especially in the low concentration range of 0.1-20 mg / L, its adsorption efficiency was significantly improved compared with the comparative example samples. This phenomenon may be closely related to the relatively high shear plane potential (+8.9 mV, pH = 7) and optimized specific surface area (89.28 m² / g) of the example, which enhanced the physical adsorption ability of the adsorbent to negatively charged phosphate ions, especially the electrostatic attraction was significantly enhanced.

[0056] According to the kinetic fitting results, the adsorption process of the examples of the present application was more in line with the pseudo-second-order kinetic model (R²>0.99), and its rate constant k2 reached 1.24 min -1 , which were 1.68 times and 2.03 times that of Comparative Example 1 (0.74 min -1 ) and Comparative Example 2 (0.61 min -1 ), respectively, indicating that the dominant mechanism of this adsorption process was chemisorption. Comparing horizontally with existing modified clay mineral adsorbents (including processes such as acid / alkali / heat treatment, metal doping, and layered double hydroxide modification), under the premise of maintaining a low dosage (<0.5 g / L), the adsorption capacity of this example reached the leading level in the clay mineral adsorption passivation industry, and its adsorption rate was significantly improved compared with similar products. This breakthrough improvement in performance was mainly due to the unique amino-functionalized modification strategy and the resulting synergistic adsorption effect.

[0057] 3. Regeneration cycle experiment In the regeneration experiment, the used NH2-La-Ben(Et) adsorbent prepared in Example 3 was dispersed in 1 M NaOH eluent at a solid-liquid ratio of 1 g / L, filtered and separated after shaking for 2 hours, rinsed with deionized water to a neutral pH, and then vacuum dried at 65 °C. Five regeneration cycle experiments were carried out. Lanthanum and phosphorus in the adsorbent were dissolved by hydrofluoric acid and detected by inductively coupled plasma optical emission spectrometer (ICP-OES, Agilent 5110).

[0058] 4. Adsorption column experiment In the adsorption column experiment, a fixed-bed adsorption column (inner diameter 10 mm, height 7 mm) was used, and the filler was 30% (mass fraction) adsorbent and 70% (mass fraction) massive dolomite. A solution containing 0.5 mg / L phosphorus was continuously transported at a constant flow rate of 6 mL / min by a peristaltic pump (BT100-2J, Lange, China) to investigate the dynamic adsorption capacity of the adsorption column for phosphorus. The regenerated adsorbent was rinsed with NaOH and deionized water to a neutral pH for the next cycle experiment.

[0059] As can be seen from Figure 4 , after 5 cycles (450 min of adsorption), the phosphorus removal rate remained above 71.1%. After two regenerations, the phosphorus concentration in the simulated wastewater could be reduced to the safe level of algal eutrophication (0.02 mg / L). After 4 cycles, the phosphorus concentration could still be reduced to 0.1 mg / L, indicating that the deep phosphorus removal material prepared in this application has good regeneration cycle stability and meets the standards of the US National Pollutant Discharge Elimination System (NPDES) and the EU Water Framework Directive (0.1 mg / L).

[0060] Regarding the material stability aspect ( Figure 5 ), there were significant differences in the leaching characteristics of La elements in Example 3 and Comparative Examples 1-2. It was found that the La dissolution degrees in Example 3 and Comparative Example 2 showed a gradient downward trend during the 350 min experimental period. It is worth noting that the cumulative dissolution degrees of Example 3 during the whole experimental period were 19.6% and 15.1% lower than those of Comparative Example 1 and Comparative Example 2 respectively. The test data fully prove that the examples of this application not only have significantly improved cyclic phosphorus removal performance, but also have significantly better leaching stability than the existing technical solutions.

[0061] To verify the actual application performance of the material, this application constructed a solution containing phosphate and competitive anions (Cl - , SO4 2- , NO3 -The simulated wastewater of ([ID=]) was used to systematically evaluate the engineering applicability of Example 3 under continuous fixed-bed operating conditions. Figure 6 The results showed that when the inlet flow rate multiples reached 1100 BV, 2500 BV, and 3500 BV respectively, the effluent phosphorus concentrations of Comparative Example 2, Comparative Example 1, and Example 3 exceeded the National Pollutant Discharge Elimination System (NPDES) standard (0.1 mg / L) successively. When the inlet flow rate multiple was increased to 3500 BV, 6500 BV, and 8000 BV, the phosphorus adsorption capacities of Comparative Example 2, Comparative Example 1, and the Example reached the saturation critical point in turn. It is worth noting that Example 3 could still maintain effective adsorption under the high hydraulic load condition of 8000 BV, and its breakthrough treatment capacities reached 1.23 times and 2.29 times that of Comparative Example 1 (6500 BV) and Comparative Example 2 (3500 BV) respectively.

[0062] To study the selective adsorption effect of this adsorbent with coexisting anions (Cl - , SO4 2- , NO3 - , HCO3 - ), adsorption experiments of Example 3, Comparative Example 1, and Comparative Example 2 for P were carried out in the simulated water body ( Figure 7 ). The distribution coefficient (K d ) is defined as the ratio of the anion concentration in the solid phase to the anion concentration in the liquid phase at the reaction equilibrium (a dimensionless constant of the adsorption capacity under the unified standard). The K d values of Example 3 (1.83) and Comparative Example 1 (0.71) for phosphate were higher than the K d values of other coexisting anions, indicating that the Example had a higher phosphate selectivity. Comparative Example 2 (0.22) showed higher K 2- values for SO4 - , NO3 - , and HCO3 d , indicating that they had poor resistance to these coexisting ions in the water body.

[0063] From the separation constant, α (relative separation constant) represents the relative separation ability of the adsorbent for the adsorbate. The α value of Comparative Example 2 was greater than 1 ( Figure 8 , 9), indicating that the adsorption of phosphate by these two adsorbents in the coexisting system was relatively low, especially with nitrate ions, sulfate ions, and bicarbonate ions. The α values of different anions in Example 3 were all less than 1, and even the lowest among the three adsorbents. To sum up, the Example showed great potential for selectively adsorbing phosphorus in low-phosphorus water bodies with multiple anions coexisting.

[0064] The interference experiment results under different coexisting ion concentrations ( Figure 10 ) showed that the Example had good resistance to Cl- and SO4 2- In the presence of (1 - 10 mM), the adsorption rate can still remain above 91.4%. High - concentration HCO3 - (10 mM) causes the adsorption rate of phosphate in water to drop sharply from 94.4% to 69.3%, and it is very difficult for lake water to reach this concentration level. As the concentration of humic acid increases, the removal rate shows a U - shaped curve, indicating that humic acid promotes the adsorption of phosphorus at low concentrations but inhibits it at high concentrations. In summary, the deep - dephosphorization material prepared in this application shows excellent tolerance in complex water bodies compared with the comparative examples, which may be related to the inner - sphere complexation of La - O - P and hydrogen - bond interactions.

Claims

1. A preparation method of a deep phosphorus removal material, characterized in that It includes at least the following steps: S1. Dissolve the lanthanide metal salt and bentonite in ethanol solution respectively, and obtain the lanthanide metal salt ethanol solution and bentonite ethanol solution after ultrasonic treatment; S2. Sequentially add the lanthanide metal salt ethanol solution and the organic silane ammonia hydrolysis solution to the magnetically dispersed bentonite ethanol solution sample, impregnate at room temperature for 6 h, and then filter to obtain a solid precipitate; S3. Wash, dry, grind and sieve the solid precipitate to obtain a deep phosphorus removal material.

2. The preparation method of the deep phosphorus removal material according to claim 1, characterized in that, The preparation method of the organic silane ammonia hydrolysis solution is: dissolve the organic silane ammonia in deionized water, and the hydrolysis time is 10 min.

3. The preparation method of the deep phosphorus removal material according to claim 2, characterized in that, The mass concentration of the organic silane ammonia in the organic silane ammonia hydrolysis solution is any one of 1.3%, 2.6%, 5.2% and 10.4%.

4. The preparation method of the deep phosphorus removal material according to claim 1, characterized in that, The conditions of the ultrasonic treatment in step S1: the ultrasonic frequency is 53 kHz, and the ultrasonic time is 10 - 20 min.

5. The preparation method of the deep phosphorus removal material according to claim 1, characterized in that, In step S1, after the bentonite is ultrasonically treated in the ethanol solution, it also needs to be subjected to high-speed dispersion treatment. The conditions of the high-speed dispersion treatment are 1000 rpm at room temperature, and the dispersion time is 20 - 30 min.

6. The preparation method of the deep phosphorus removal material according to claim 1, characterized in that, The conditions of the magnetic dispersion in step S2 are magnetic stirring at room temperature, and the rotation speed is 200 rpm.

7. The preparation method of the deep phosphorus removal material according to claim 1, characterized in that, The lanthanide metal salt includes lanthanum chloride.

8. The preparation method of the deep phosphorus removal material according to claim 1, characterized in that, The organic silane ammonia includes 3-(phenylamino)propyltrimethoxysilane.

9. A deep phosphorus removal material prepared by the preparation method according to any one of claims 1 - 8.

10. Use of the deep phosphorus removal material according to claim 9, characterized in that, It is applied to the removal of phosphate in water bodies.

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