Nano-modified efficient flocculated aluminum chloride water treatment agent and preparation method thereof

Abstract

The invention discloses a nano-modified efficient flocculated aluminum chloride water treatment agent and a preparation method thereof, and belongs to the technical field of sewage treatment. The nano-modified efficient flocculated aluminum chloride water treatment agent comprises modified montmorillonite and polyaluminum chloride in a mass ratio of (1-3): (1-3), and the modified montmorillonite is compounded with the polyaluminum chloride, so that the flocculation performance of the water treatment agent is remarkably improved; the water treatment agent not only can greatly improve the adsorption, capture and sedimentation efficiency of various pollutants such as suspended solids, colloidal substances and heavy metals in water and realize a higher water purification effect, but also has higher stability and dispersity, and can keep an efficient effect under different water quality conditions. Compared with the traditional polyaluminum chloride flocculant, the product has the advantages of lower dosage, high floc forming speed and favorable settling property, is convenient for subsequent solid-liquid separation and treatment, and integrally improves the economical efficiency and environmental friendliness of the water treatment process.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and particularly relates to a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent and a preparation method thereof. Background Art

[0002] As an important inorganic polymer flocculant, polyaluminum chloride has become one of the most widely used flocculants at present because it has higher positive charges, stronger adsorption bridging ability, a wider suitable pH range, larger and faster-settling flocs, less dosage, less corrosion, and significant effects in treating low-temperature and low-turbidity water compared with traditional aluminum salts (such as aluminum sulfate). The chemical general formula of polyaluminum chloride is generally expressed as [Al2(OH) n Cl 6-n m , which is a cationic inorganic polymer flocculant with multiple hydroxyl groups and polynuclear complexes. Its flocculation effect mainly depends on the morphological distribution of aluminum ions, especially the content of polynuclear hydroxyl complexes with high polymerization degrees such as Al13 and Al30. Although polyaluminum chloride has achieved remarkable results in water treatment, for some wastewater with complex components, slightly polluted source water, and low-temperature and low-turbidity water, the flocculation effect of traditional PAC is sometimes not ideal, and the removal rate of heavy metal ions is not high; when treating wastewater with high turbidity or high organic matter content, the dosage of PAC is large, increasing the treatment cost and sludge production.

[0003] Chinese Patent Document CN116969535A discloses a sewage treatment agent containing polyaluminum chloride and a preparation method thereof. The preparation method of the sewage treatment agent containing polyaluminum chloride consists of the following steps: primary treatment, secondary treatment, and preparation; the primary treatment consists of the following steps: premixing, plasma modification, and cationic modification. The sewage treatment agent containing polyaluminum chloride of the present invention can achieve good sewage treatment effects in a low water temperature environment. The sewage treatment agent containing polyaluminum chloride has good dispersion in low-temperature water and high sewage treatment efficiency; at the same time, it can also effectively improve the adaptability and treatment effect of the sewage treatment agent to acidic or alkaline sewage, and can maintain good sewage treatment effects and treatment efficiency in acidic or alkaline sewage; the functional carriers of this patent are activated carbon and nano-silica. Although plasma and surface cationic modifications are carried out, the types and densities of functional groups are limited, and the efficient removal of organic pollutants and heavy metal ions cannot be achieved, resulting in the defect that its flocculation effect needs to be further improved. Summary of the Invention

[0004] ​The main object of the present invention is to provide a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent and its preparation method. The water treatment agent combines the characteristics of inorganic and organic flocculants. By blending modified montmorillonite with polyaluminum chloride, the high specific surface area of the modified montmorillonite provides a good carrier for polyaluminum chloride, and forms a spatial network structure synergistically with polyaluminum chloride during the flocculation process, enhancing the particle capture and agglomeration sedimentation rate. A large number of active groups on the surface of the modified montmorillonite can have multiple interactions with pollutants, achieving the capture of inorganic suspended solids, organic matter and heavy metals.

[0005] To achieve the above object, the present invention provides a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent, comprising modified montmorillonite and polyaluminum chloride, and the mass ratio of the two is 1-3:1-3.

[0006] Preferably, the preparation method of the modified montmorillonite comprises the following steps: 1) Dissolve xanthan gum in hot water, add epichlorohydrin and polyethyleneimine, heat and react, then cool and filter. Freeze-dry the solid to obtain pretreated xanthan gum; 2) Disperse montmorillonite in a mixed solution of ethanol and water, add γ-glycidoxypropyltrimethoxysilane, stir and react, filter and collect the solid, wash and dry to obtain epoxy-group montmorillonite; 3) Disperse the epoxy-group montmorillonite in water, add the pretreated xanthan gum, raise the temperature and react for a period of time, filter, collect the solid and add it to N,N-dimethylformamide, then add 1-(carboxymethyl)-3-methylimidazolium chloride, 3-thiophene malonic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, N-hydroxysuccinimide, reflux and react, filter, collect the solid, wash and dry to obtain modified montmorillonite.

[0007] Preferably, in the step 1), the mass ratio of xanthan gum, epichlorohydrin and polyethyleneimine is 12-18:5-8:10-15; the heating reaction temperature is 80-95°C, and the reaction time is 2-4 h.

[0008] Xanthan gum is a natural organic polymer flocculant. Its molecular structure contains multiple active hydroxyl groups. Under the action of epichlorohydrin, the polyamino compound polyethyleneimine is grafted onto xanthan gum, increasing the cation density and the number of active groups on the xanthan gum molecular chain, enhancing the bridging effect and adsorption capacity with pollutants. On the one hand, it improves the flocculation performance of xanthan gum, and on the other hand, it is beneficial to subsequent reactions.

[0009] Preferably, in the step 2), the mass ratio of montmorillonite and γ-glycidoxypropyltrimethoxysilane is 15-24:4-8; the stirring reaction temperature is 40-60°C, and the reaction time is 3-5 h.

[0010] By treating montmorillonite with γ-glycidyl ether oxypropyltrimethoxysilane to introduce epoxy groups on its surface, the agglomeration of montmorillonite is avoided, and it is also beneficial to react with pretreated xanthan gum.

[0011] Preferably, in the step 3), the mass ratio of epoxy montmorillonite, pretreated xanthan gum, 1-(carboxymethyl)-3-methylimidazolium chloride, and 3-thiophene malonic acid is 6-10:2-3:1-2:1.2-2.2; the temperature for the heating reaction is 50-80 °C, and the reaction time is 5-7 h; the concentration of EDC in the EDC / NHS aqueous solution is 30-40 mM / L, and the concentration of NHS is 40-50 mM / L; the temperature for the reflux reaction is 50-60 °C, and the reaction time is 6-8 h.

[0012] In this step, the epoxy groups on the epoxy montmorillonite react with the hydroxyl and amino groups on the pretreated xanthan gum to combine the pretreated xanthan gum with montmorillonite to form a stable organic-inorganic hybrid material. This material has both a high specific surface area, structural stability, and multifunctional surface activity. It can not only improve the adsorption capacity of organic pollutants but also synergistically capture inorganic suspended solids and heavy metals. Then, it reacts with 1-(carboxymethyl)-3-methylimidazolium chloride and 3-thiophene malonic acid under the activation of the EDC / NHS aqueous solution to graft 1-(carboxymethyl)-3-methylimidazolium chloride and 3-thiophene malonic acid onto montmorillonite; 1-(carboxymethyl)-3-methylimidazolium chloride has good ion exchange and charge regulation capabilities, and 3-thiophene malonic acid is rich in sulfur heterocycles and conjugated structures, which can complex heavy metal ions in water and form π-π conjugation with benzene ring-containing organic compounds to remove heavy metal ions and benzene ring-containing organic compounds in water.

[0013] The present invention also discloses a preparation method of the nano-modified highly efficient flocculating polyaluminum chloride water treatment agent, which includes the following steps: uniformly mixing modified montmorillonite, polyaluminum chloride, and water, then performing ultrasonic heating treatment, filtering, collecting the solid matter, drying, grinding, and sieving to obtain the nano-modified highly efficient flocculating polyaluminum chloride water treatment agent.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention provides a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent. By compounding modified montmorillonite with polyaluminum chloride, the flocculation performance of the water treatment agent is significantly improved. This water treatment agent can not only greatly improve the adsorption, capture, and sedimentation efficiency of various pollutants such as suspended solids, colloidal substances, and heavy metals in water to achieve a higher water purification effect, but also has high stability and dispersibility, and can maintain high efficiency under different water quality conditions. Compared with traditional flocculants, this product has a lower dosage, a fast floc formation speed, good sedimentation performance, which is convenient for subsequent solid-liquid separation and treatment, and overall improves the economy and environmental protection of the water treatment process; (2) The nano-modified highly efficient flocculating polyaluminum chloride water treatment agent of the present invention combines the characteristics of inorganic and organic flocculants. By blending modified montmorillonite with polyaluminum chloride, the high specific surface area of the modified montmorillonite provides a good carrier for polyaluminum chloride, and forms a spatial network structure synergistically with polyaluminum chloride during the flocculation process, enhancing the particle capture and agglomeration sedimentation rate. A large number of active groups (hydroxyl, amino, imidazole, and thiophene) on the surface of the modified montmorillonite can have multiple interactions with pollutants, realizing the capture of inorganic suspended solids, organic matter, and heavy metals, and constructing a highly efficient purification network of hydrophilic-hydrophobic hybridization. Relying on the synergistic effect of multiple flocculants, the various active functional groups on the surfaces of polyaluminum chloride and modified montmorillonite act together, complementing each other in terms of electricity and structure, effectively jointly capturing and stabilizing various negatively charged colloids and impurities in water, improving the formation rate and sedimentation performance of flocs. By grafting polyethyleneimine, 1-(carboxymethyl)-3-methylimidazolium chloride, and 3-thiophene malonic acid onto montmorillonite, the risk of its remaining in water is greatly reduced, promoting the filtration and dehydration effects of flocs, and improving the efficiency and environmental friendliness of the water treatment process. Detailed implementation mode

[0015] To avoid repetition, unless otherwise specified, the items used in the following examples are all commercially available products, and the methods used are all conventional methods unless otherwise specified.

[0016] The sources of some raw materials used in the present invention are as follows: Montmorillonite, sodium-based, 325 mesh, purchased from Yang's Mineral Products Co., Ltd., Lingshou County.

[0017] Xanthan gum, with a content of 99%, purchased from Jiangsu Weizhirun Biotechnology Co., Ltd.

[0018] Polyaluminum chloride, 200 mesh, purchased from Henan Shuibiqing Environmental Protection Technology Co., Ltd.

[0019] Example 1 A preparation method of a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent includes the following steps: Mix 20 g of modified montmorillonite, 20 g of polyaluminum chloride, and 100 g of water evenly, heat and ultrasonically treat at 80 °C for 30 min, filter, collect the solid matter, dry, grind, and sieve to obtain the nano-modified highly efficient flocculating polyaluminum chloride water treatment agent.

[0020] The preparation method of the modified montmorillonite includes the following steps: 1) Dissolve 15 g of xanthan gum in 200 mL of hot water at 80 °C, add 6.8 g of epichlorohydrin and 12.6 g of polyethyleneimine, heat and react at 90 °C for 2 h, then cool and filter. Freeze-dry the solid matter to obtain pretreated xanthan gum; 2) Disperse 20 g of montmorillonite in a mixed solution composed of 100 mL of ethanol and 100 mL of water, add 5.3 g of γ-glycidoxypropyltrimethoxysilane, stir and react at 50 °C for 4 h, filter to collect the solid, wash and dry it to obtain epoxy montmorillonite; 3) Disperse 16 g of epoxy montmorillonite in 200 mL of water, add 5 g of pretreated xanthan gum, heat up to 80 °C and react for 6 h, filter, add the collected solid to 200 mL of N,N-dimethylformamide, then add 3 g of 1-(carboxymethyl)-3-methylimidazolium chloride, 4 g of 3-thiophene malonic acid, 3.6 g of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, 2.5 g of N-hydroxysuccinimide, reflux and react at 55 °C for 7 h, filter, collect the solid, wash and dry it to obtain modified montmorillonite.

[0021] Example 2 A preparation method of a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent, comprising the following steps: Mix 10 g of modified montmorillonite, 20 g of polyaluminum chloride, and 100 g of water evenly, heat and ultrasonically treat at 80 °C for 30 min, filter, collect the solid, dry, grind, and sieve to obtain the nano-modified highly efficient flocculating polyaluminum chloride water treatment agent.

[0022] The preparation method of the modified montmorillonite comprises the following steps: 1) Dissolve 12 g of xanthan gum in 200 mL of 80 °C hot water, add 5.1 g of epichlorohydrin and 10 g of polyethyleneimine, heat and react at 80 °C for 2 h, then cool and filter. Freeze-dry the solid to obtain pretreated xanthan gum; 2) Disperse 15 g of montmorillonite in a mixed solution composed of 100 mL of ethanol and 100 mL of water, add 4 g of γ-glycidoxypropyltrimethoxysilane, stir and react at 50 °C for 4 h, filter to collect the solid, wash and dry it to obtain epoxy montmorillonite; 3) Disperse 12 g of epoxy montmorillonite in 200 mL of water, add 4 g of pretreated xanthan gum, heat up to 80 °C and react for 6 h, filter, add the collected solid to 200 mL of N,N-dimethylformamide, then add 2 g of 1-(carboxymethyl)-3-methylimidazolium chloride, 2.4 g of 3-thiophene malonic acid, 3.2 g of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, 2.2 g of N-hydroxysuccinimide, reflux and react at 55 °C for 7 h, filter, collect the solid, wash and dry it to obtain modified montmorillonite.

[0023] Example 3 A preparation method of a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent, comprising the following steps: Mix 30 g of modified montmorillonite, 10 g of polyaluminum chloride, and 100 g of water evenly, then heat and ultrasonically treat the mixture at 80 °C for 30 min, filter, collect the solid matter, dry, grind, and sieve it to obtain the nano-modified highly efficient flocculating polyaluminum chloride water treatment agent.

[0024] The preparation method of the modified montmorillonite comprises the following steps: 1) Dissolve 18 g of xanthan gum in 200 mL of 80 °C hot water, add 8 g of epichlorohydrin and 15 g of polyethyleneimine, heat and react at 90 °C for 2 h, then cool and filter. Freeze-dry the solid matter to obtain pretreated xanthan gum; 2) Disperse 24 g of montmorillonite in a mixed solution composed of 100 mL of ethanol and 100 mL of water, add 8 g of γ-glycidoxypropyltrimethoxysilane, stir and react at 50 °C for 4 h, filter, collect the solid matter, wash and dry it to obtain epoxy-group montmorillonite; 3) Disperse 20 g of epoxy-group montmorillonite in 200 mL of water, add 6 g of pretreated xanthan gum, raise the temperature to 80 °C and react for 6 h, filter, collect the solid matter, add it to 200 mL of N,N-dimethylformamide, then add 4 g of 1-(carboxymethyl)-3-methylimidazolium chloride, 4.4 g of 3-thiophenepropanedioic acid, 4 g of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, and 3 g of N-hydroxysuccinimide, reflux and react at 55 °C for 7 h, filter, collect the solid matter, wash and dry it to obtain the modified montmorillonite.

[0025] Comparative Example 1 A preparation method of a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent, similar to Example 1, except that 3-thiophenepropanedioic acid is not grafted onto the modified montmorillonite. Specifically, it comprises the following steps: Mix 20 g of modified montmorillonite, 20 g of polyaluminum chloride, and 100 g of water evenly, then heat and ultrasonically treat the mixture at 80 °C for 30 min, filter, collect the solid matter, dry, grind, and sieve it to obtain the nano-modified highly efficient flocculating polyaluminum chloride water treatment agent.

[0026] The preparation method of the modified montmorillonite comprises the following steps: 1) Dissolve 15 g of xanthan gum in 200 mL of 80 °C hot water, add 6.8 g of epichlorohydrin and 12.6 g of polyethyleneimine, heat and react at 90 °C for 2 h, then cool and filter. Freeze-dry the solid matter to obtain pretreated xanthan gum; 2) Disperse 20 g of montmorillonite in a mixed solution composed of 100 mL of ethanol and 100 mL of water, add 5.3 g of γ-glycidoxypropyltrimethoxysilane, stir and react at 50 °C for 4 h, filter, collect the solid matter, wash and dry it to obtain epoxy-group montmorillonite; 3) Disperse 16 g of epoxy montmorillonite in 200 mL of water, add 5 g of pretreated xanthan gum, heat to 80 °C and react for 6 h, filter, collect the solid matter, add it to 200 mL of N,N-dimethylformamide, then add 3 g of 1-(carboxymethyl)-3-methylimidazolium chloride, 3.6 g of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, and 2.5 g of N-hydroxysuccinimide, reflux and react at 55 °C for 7 h, filter, collect the solid matter, wash and dry to obtain modified montmorillonite.

[0027] Comparative Example 2 A preparation method of a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent is similar to Example 1, the difference being that 1-(carboxymethyl)-3-methylimidazolium chloride is not grafted onto the modified montmorillonite. The specific steps are as follows: Mix 20 g of modified montmorillonite, 20 g of polyaluminum chloride, and 100 g of water evenly, heat and ultrasonically treat at 80 °C for 30 min, filter, collect the solid matter, dry, grind, and sieve to obtain the nano-modified highly efficient flocculating polyaluminum chloride water treatment agent.

[0028] The preparation method of the modified montmorillonite includes the following steps: 1) Dissolve 15 g of xanthan gum in 200 mL of 80 °C hot water, add 6.8 g of epichlorohydrin and 12.6 g of polyethyleneimine, heat and react at 90 °C for 2 h, then cool and filter. Freeze-dry the solid matter to obtain pretreated xanthan gum. 2) Disperse 20 g of montmorillonite in a mixed solution composed of 100 mL of ethanol and 100 mL of water, add 5.3 g of γ-glycidoxypropyltrimethoxysilane, stir and react at 50 °C for 4 h, filter, collect the solid matter, wash and dry to obtain epoxy montmorillonite. 3) Disperse 16 g of epoxy montmorillonite in 200 mL of water, add 5 g of pretreated xanthan gum, heat to 80 °C and react for 6 h, filter, collect the solid matter, add it to 200 mL of N,N-dimethylformamide, then add 4 g of 3-thiophene malonic acid, 3.6 g of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, and 2.5 g of N-hydroxysuccinimide, reflux and react at 55 °C for 7 h, filter, collect the solid matter, wash and dry to obtain modified montmorillonite.

[0029] Comparative Example 3 A preparation method of a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent is similar to Example 1, the difference being that the pretreated xanthan gum is not combined with the modified montmorillonite. The specific steps are as follows: Mix 20 g of modified montmorillonite, 20 g of polyaluminum chloride, and 100 g of water evenly, heat and ultrasonically treat at 80 °C for 30 min, filter, collect the solid matter, dry, grind, and sieve to obtain the nano-modified highly efficient flocculating polyaluminum chloride water treatment agent.

[0030] The preparation method of the modified montmorillonite comprises the following steps: 1) Disperse 20 g of montmorillonite in a mixed solution composed of 100 mL of ethanol and 100 mL of water, add 5.3 g of γ-glycidoxypropyltrimethoxysilane, and stir and react at 50 °C for 4 h. Filter and collect the solid, wash and dry it to obtain epoxy montmorillonite; 2) Disperse 16 g of epoxy montmorillonite in 200 mL of N,N-dimethylformamide, then add 3 g of 1-(carboxymethyl)-3-methylimidazolium chloride, 4 g of 3-thiophene malonic acid, 3.6 g of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, and 2.5 g of N-hydroxysuccinimide. Reflux and react at 55 °C for 7 h, filter, and collect the solid, wash and dry it to obtain the modified montmorillonite.

[0031] Performance test Take the sewage from a certain industrial park as the test water. The initial COD of the test water cr is 5367 mg / L, the ammonia nitrogen content is 1356 mg / L, the suspended solid content is 0.47 g / L, the total phosphorus content is 0.38 mg / L, the total chromium content is 1.2 mg / L, and the pH value is 8.6. Respectively use the nano-modified highly efficient flocculant polyaluminum chloride water treatment agents of Examples 1-3 and Comparative Examples 1-3 to treat the test water at a water temperature of 10 °C, and control the dosage of the nano-modified highly efficient flocculant polyaluminum chloride water treatment agent to be 1 g / L. After the treatment of the test water is completed, detect the various indexes in the treated test water and calculate the removal rate of the corresponding indexes. The calculation method of the removal rate is: [(initial content - content after treatment) / initial content]×100%. The test results are shown in Table 1: Table 1 Performance test results of nano-modified highly efficient flocculant polyaluminum chloride water treatment agent It can be seen from the experimental results in Table 1 that the nano-modified highly efficient flocculant polyaluminum chloride water treatment agent prepared by the present invention has a good flocculation effect.

[0032] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the patent protection scope of the present invention.

Claims

1. A nano-modified highly efficient flocculating polyaluminum chloride water treatment agent, characterized in that, It includes modified montmorillonite and polyaluminum chloride, and the mass ratio of the modified montmorillonite to the polyaluminum chloride is 1 - 3:1 - 3.

2. The water treatment agent according to claim 1, wherein The preparation method of the modified montmorillonite includes the following steps: 1) Dissolve xanthan gum in hot water, add epichlorohydrin and polyethyleneimine, heat and react, then cool and filter. Freeze-dry the solid to obtain pretreated xanthan gum. 2) Disperse montmorillonite in a mixed solution of ethanol and water, add γ-glycidoxypropyltrimethoxysilane, stir and react, filter and collect the solid, wash and dry to obtain epoxy-group montmorillonite. 3) Disperse the epoxy-group montmorillonite in water, add the pretreated xanthan gum, raise the temperature and react for a period of time, filter, collect the solid and add it to N,N-dimethylformamide, then add 1-(carboxymethyl)-3-methylimidazolium chloride, 3-thiophene malonic acid, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, N-hydroxysuccinimide, reflux and react, filter, collect the solid, wash and dry to obtain the modified montmorillonite.

3. The water treatment agent according to claim 2, characterized in that: In the step 1), the mass ratio of xanthan gum, epichlorohydrin and polyethyleneimine is 12 - 18:5 - 8:10 - 15.

4. The water treatment agent according to claim 2, wherein: In the step 1), the heating reaction temperature is 80 - 95 °C and the reaction time is 2 - 4 h.

5. The water treatment agent according to claim 2, characterized in that: In the step 2), the mass ratio of montmorillonite to γ-glycidoxypropyltrimethoxysilane is 15 - 24:4 - 8.

6. The water treatment agent according to claim 2, wherein: In the step 2), the stirring reaction temperature is 40 - 60 °C and the reaction time is 3 - 5 h.

7. The water treatment agent according to claim 2, characterized in that: In the step 3), the mass ratio of epoxy-group montmorillonite, pretreated xanthan gum, 1-(carboxymethyl)-3-methylimidazolium chloride and 3-thiophene malonic acid is 6 - 10:2 - 3:1 - 2:1.2 - 2.

2.

8. The water treatment agent according to claim 2, wherein: In the step 3), the temperature-raising reaction temperature is 50 - 80 °C and the reaction time is 5 - 7 h.

9. The water treatment agent according to claim 2, characterized in that: The reflux reaction temperature is 50 - 60 °C and the reaction time is 6 - 8 h.

10. A method for preparing the water treatment agent according to any one of claims 1-9, characterized in that, It includes the following steps: Mix the modified montmorillonite, polyaluminum chloride and water evenly, then perform ultrasonic heating treatment, filter, collect the solid, dry, grind and sieve to obtain a nano-modified highly efficient flocculating polyaluminum chloride water treatment agent.

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