Preparation method and application of modified mineral-based material capable of targeted adsorption of phosphorus

Abstract

The application discloses a preparation method and application of a modified mineral-based material capable of targeted adsorption of phosphorus, and steps are as follows: 1) soaking mineral material, i.e., sodium mica, in distilled water for 2-4 hours; 2) adding the pretreated sodium mica into a diethylene triamine pentaacetic acid solution, and stirring under microwave-assisted water bath heating for 1-2 hours; 3) stirring in a ZrOCl2 solution for 1-2 hours, and drying in an electric heating constant-temperature drying oven until a constant weight is obtained, so as to prepare carboxyl functionalized metal-based modified sodium mica. The application also relates to application of the modified mineral-based material capable of targeted adsorption of phosphorus to treatment of phosphorus-containing sewage. The method is easy and simple to operate, the material is convenient to use, environment-friendly, can realize targeted and efficient selective removal of phosphate in water, can be used in a solution containing NO3 ‑ , SO4 2‑ and Cl ‑ and PO4 3‑ , is not affected by coexisting ions, can target and efficiently adsorb phosphorus, and has the advantages of a removal rate of phosphorus of 98.5% or more and good targeted adsorption effect of phosphorus.

Description

Technical Field

[0001] This invention belongs to the field of water treatment engineering and environmental protection material preparation technology, and more specifically relates to a method for preparing a modified mineral-based material that can target phosphorus adsorption, and also relates to the use of a modified mineral-based material that can target phosphorus adsorption, which can be applied to the treatment of phosphorus-containing wastewater. Background Technology

[0002] Eutrophication has become a global water pollution problem. Eutrophication degrades water quality, leading to excessive growth of algae and other harmful plankton, depletion of dissolved oxygen, water degradation, decreased water transparency, and a decline in the numbers of aquatic animals such as fish and shrimp. This disrupts and imbalances the aquatic ecosystem, severely impacting human development and quality of life. Phosphorus, due to its nutrient-limiting role in aquatic ecosystems, is a key factor contributing to eutrophication.

[0003] Natural water bodies and wastewater contain a large number of anions, cations, organic matter, and microorganisms. Commonly used adsorbents are easily affected by coexisting substances (such as anions) during phosphate removal. Furthermore, the typical concentration of phosphate in water and wastewater is usually lower than the concentration of other coexisting anions. In the presence of a large number of competing anions, selective phosphate removal becomes more difficult, resulting in lower phosphate removal efficiency. Simultaneously, the purity of the phosphate recovery solution obtained through adsorbent regeneration is low, affecting its subsequent treatment. Therefore, selective adsorption of phosphate is necessary, avoiding the adsorption of other coexisting substances (such as anions) while adsorbing phosphate, to achieve targeted, efficient, and selective phosphate removal. Summary of the Invention

[0004] The purpose of this invention is to address the technical bottleneck of selectively removing phosphorus from wastewater, and to provide a method for preparing modified mineral-based materials that can target phosphorus adsorption. The method is easy to implement and simple to operate. The prepared material has the advantages of being convenient to use, environmentally friendly, achieving a phosphorus removal rate of over 98.5%, and having a good targeted phosphorus adsorption effect.

[0005] Another objective of this invention is to provide an application of a modified mineral-based material capable of targeted phosphorus adsorption in the treatment of phosphorus-containing wastewater, essentially achieving targeted and efficient selective removal of phosphates from water bodies. This material can be used in wastewater containing NO3-. - SO4 2- and Cl - With PO4 3- In solutions containing numerous coexisting ions, it is largely unaffected by these ions, effectively and efficiently adsorbing phosphorus with a phosphorus removal rate exceeding 98.5%.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for preparing a modified mineral-based material capable of targeted phosphorus adsorption, comprising the following steps:

[0008] 1) Treatment of the mineral material sodium mica: Soak the mineral material sodium mica (particle size 2-5mm) in distilled water for 2-4 hours;

[0009] 2) Heating and stirring: Add the pretreated sodium mica to a diethyltriaminepentaacetic acid (DTPA) solution (mass fraction 2%-8%) and heat and stir in a microwave-assisted water bath (50℃-70℃) for 1-2 hours;

[0010] 3) Place it in a zirconium dioxide (ZrOCl2) solution (mass fraction 0.5%-2%) and stir for 1-2 hours. Then place it in an electric thermostatic drying oven and dry it to constant weight to prepare carboxyl functionalized metal-based modified sodium mica.

[0011] Natural water bodies and wastewater contain a large number of anions, cations, organic matter, and microorganisms. Commonly used adsorbents are easily affected by coexisting substances during phosphate removal. Furthermore, the typical concentration of phosphate in water and wastewater is usually lower than the concentration of other coexisting anions. In the presence of a large number of competing anions, selective phosphate removal becomes more difficult, resulting in lower phosphate removal efficiency. Simultaneously, the purity of the phosphate recovery solution obtained through adsorbent regeneration is low, affecting its subsequent treatment. Therefore, the most crucial step in this invention is step 2), which involves grafting diethylenetriaminepentaacetic acid (DTPA) onto the surface of sodium mica, increasing the presence of carboxyl groups (-COOH) and other organic functional groups as hydrogen bond acceptors, and utilizing hydrogen bonding to achieve selective phosphate removal. This key step solves the problems and difficulties of low phosphate removal efficiency when conventional mineral-based materials remove phosphorus through physical adsorption and chemical reactions, especially when wastewater contains a large number of competing anions. Through this key step, phosphate can be removed in a targeted and efficient manner even when there are a large number of competing anions such as sulfate, nitrate, chloride, and fluoride ions. Selective and targeted removal of phosphate is achieved by using hydrogen bonding, with a removal rate of over 98.0%.

[0012] The main advancements and differences of this invention compared to existing technologies are as follows: Existing technologies often improve the adsorption capacity of adsorbent materials by modifying their surface charge or metal loading, which can be applied to treat wastewater containing only phosphorus. However, for wastewater containing multiple competing anions, the removal efficiency is difficult to meet satisfactory requirements. This invention, based on the differences in surface charge, acid-base properties, geometry, and metal complexing ability between phosphate and other coexisting ions, involves adding pretreated sodium mica to a diethylenetriaminepentaacetic acid (DTPA) solution for grafting via microwave-assisted water bath heating. Then, it undergoes targeted modification through impregnation in a zirconium dioxide (ZrOCl2) solution, resulting in carboxyl-functionalized metal-based modified sodium mica. Unaffected by a large number of competing anions such as sulfate, nitrate, chloride, and fluoride ions, it achieves selective and targeted removal of phosphate. In solutions with numerous coexisting ions, it efficiently adsorbs phosphorus, achieving a phosphorus removal rate of over 98.5%.

[0013] The application of a modified mineral-based material capable of targeted phosphorus adsorption in the treatment of phosphorus-containing wastewater comprises the following steps:

[0014] A. Place the prepared modified mineral-based material inside the adsorption column;

[0015] B. Phosphorus-containing wastewater is injected into an adsorption column, where it is treated using modified mineral-based materials;

[0016] C. After reacting for a period of time, 1-6 hours, wastewater is discharged to achieve the purpose of targeted removal of phosphates;

[0017] D. The phosphorus-containing mineral-based materials after the reaction can be recycled.

[0018] Sodium mica is a novel mineral raw material, belonging to the mica group of minerals, and is a silicate of sodium and aluminum. It is a rock-forming mineral, widely distributed as a minor mineral in metamorphic rocks, and is prevalent in schist, phyllite, gneiss, quartz veins, and fine-grained sedimentary rocks. Based on the differences in surface charge, acid-base properties, geometry, and metal complexing ability of phosphates and other coexisting ions, pretreated sodium mica is first added to a diethylenetriaminepentaacetic acid (DTPA) solution for grafting via microwave-assisted water bath heating. Then, it undergoes targeted modification processes such as impregnation in an aqueous solution containing metal ions to prepare carboxyl-functionalized metal-based modified sodium mica. This modified mica can efficiently adsorb phosphorus in solutions containing numerous coexisting ions, achieving a phosphorus removal rate of over 98.5%.

[0019] Compared with the prior art, the present invention has the following advantages and effects:

[0020] 1. The preparation method of the adsorbent material is easy to implement, simple to operate, environmentally friendly, and does not pollute water bodies;

[0021] 2. It can target and efficiently adsorb phosphorus in solutions with many coexisting ions, achieving a phosphorus removal rate of over 98.5%. Detailed Implementation

[0022] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.

[0023] Example 1:

[0024] A method for preparing a modified mineral-based material capable of targeted phosphorus adsorption, comprising the following steps:

[0025] 1) Select sodium mica with a particle size of 2-5 mm and soak it in distilled water for 2 hours;

[0026] 2) Sodium mica soaked in distilled water was added to a 5% (w / w) solution of diethylenetriaminepentaacetic acid (DTPA) and heated and stirred in a microwave-assisted water bath at 500 MHz for 1 hour, with the water bath temperature set at 50 ℃.

[0027] 3) Place it in a 1% zirconium dioxide (ZrOCl2) solution and stir for 1 hour. Then place it in an electric thermostatic drying oven (60℃) and dry it to constant weight to prepare carboxyl functionalized metal-based modified sodium mica.

[0028] The carboxyl-functionalized metal-based modified sodium mica prepared by the above technical measures is not affected by a large number of competing anions such as sulfate, nitrate, chloride and fluoride ions, and can achieve selective and targeted removal of phosphate. In solutions with many coexisting ions, it can target and efficiently adsorb phosphorus, with a phosphorus removal rate of over 98.5%.

[0029] Example 2:

[0030] The application of a modified mineral-based material capable of targeted phosphorus adsorption in the treatment of phosphorus-containing wastewater comprises the following steps:

[0031] A. Place the modified mineral-based material prepared in Example 1 into an adsorption column;

[0032] B. Phosphorus-containing wastewater is injected into the adsorption column, and NO3 in the wastewater... - SO4 2- and Cl - With PO4 3- The concentration of all samples was 2 mg / L, and the wastewater was treated using modified mineral-based materials.

[0033] C. After reacting for 2 hours, wastewater is discharged to treat PO4. 3- The removal rate was 98.9%. When the coexisting ion concentration was NO3... - SO42- and Cl - When the concentration is further increased to 5 mg / L, the coexisting ions have virtually no effect on PO4. 3- The removal of PO4 by the modified mineral-based material of the present invention 3- The removal rate can still be maintained at over 98.5%;

[0034] D. The phosphorus-containing mineral-based materials after the reaction can be recycled and utilized as phosphate fertilizer for flowers.

[0035] Example 3:

[0036] A method for preparing a modified mineral-based material capable of targeted phosphorus adsorption, comprising the following steps:

[0037] 1) Select sodium mica with a particle size of 2-5 mm and soak it in distilled water for 4 hours;

[0038] 2) Sodium mica soaked in distilled water was added to a DTPA solution with a mass fraction of 8% and heated and stirred in a microwave-assisted water bath at a frequency of 500MHz for 2 hours. The water bath temperature was set to 50℃.

[0039] 3) Place it in a 2% zirconium dioxide (ZrOCl2) solution and stir for 2 hours. Then place it in an electric thermostatic drying oven (60℃) and dry it to constant weight to prepare carboxyl functionalized metal-based modified sodium mica.

[0040] The carboxyl-functionalized metal-based modified sodium mica prepared by the above technical measures is not affected by a large number of competing anions such as sulfate, nitrate, chloride and fluoride ions, and can achieve selective and targeted removal of phosphate. In solutions with many coexisting ions, it can target and efficiently adsorb phosphorus, with a phosphorus removal rate of over 99.5%.

[0041] Example 4:

[0042] The application of a modified mineral-based material capable of targeted phosphorus adsorption in the treatment of phosphorus-containing wastewater comprises the following steps:

[0043] A. Place the modified mineral-based material prepared in Example 3 into an adsorption column;

[0044] B. Phosphorus-containing wastewater is injected into the adsorption column, and NO3 in the wastewater... - SO4 2- and Cl - With PO4 3- The concentration of all samples was 1 mg / L, and the wastewater was treated using modified mineral-based materials.

[0045] C. After 6 hours of reaction, wastewater is discharged to treat PO4. 3- The removal rate was 99.6%. When the coexisting ion concentration was NO3...- SO4 2- and Cl - When the concentration is further increased to 5 mg / L, the coexisting ions have virtually no effect on PO4. 3- The removal of PO4 by the modified mineral-based material of the present invention 3- The removal rate can still be maintained at over 98.9%;

[0046] D. The phosphorus-containing mineral-based materials after the reaction can be recycled and utilized as phosphate fertilizer for flowers.

Claims

1. A method for preparing a modified mineral-based material capable of targeted phosphorus adsorption, comprising the following steps: 1) Treatment of the mineral material sodium mica: Soak the mineral material sodium mica with a particle size of 2-5mm in distilled water for 2-4 hours; 2) Heating and stirring: Add the pretreated sodium mica to a diethylenetriaminepentaacetic acid solution with a mass fraction of 2%-8%, and heat and stir in a microwave-assisted water bath at 50℃-70℃ for 1-2 hours; 3) Place in a zirconium dioxide solution: 0.5%-2% by mass, stir for 1-2 hours, and dry in an electric thermostatic drying oven to constant weight to prepare carboxyl functionalized metal-based modified sodium mica.

2. The application of the modified mineral-based material capable of targeted phosphorus adsorption as described in claim 1 in the treatment of phosphorus-containing wastewater, comprising the following steps: A. Place the prepared modified mineral-based material inside the adsorption column; B. Phosphorus-containing wastewater is injected into an adsorption column, where it is treated using modified mineral-based materials; C. After reacting for 1-6 hours, wastewater is discharged to achieve the purpose of targeted removal of phosphates; D. Recycling and reuse of phosphorus-containing mineral-based materials after the reaction.