Efficient aluminum sulfate treating agent with catalysis-flocculation synergistic effect

Abstract

The invention discloses an efficient aluminum sulfate treating agent with a catalysis-flocculation synergistic effect, and belongs to the technical field of wastewater treatment. The efficient aluminum sulfate treatment agent comprises the following components: a composite catalysis-flocculation material and aluminum sulfate, and solves the problems that a traditional single flocculant is limited in efficiency and narrow in application range in wastewater treatment. Through the synergistic effect of organic and inorganic flocculants and introduction of a composite material with photocatalysis and flocculation performance, the removal efficiency of suspended solids, heavy metal ions and organic matters in a water body is effectively improved, and synergistic treatment of various pollutants is realized; the treatment agent is simple in preparation process, mild in process condition and low in cost, has good environmental and economic benefits, and is suitable for purification treatment of industrial wastewater, urban sewage and complex water bodies.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment, and in particular to a high-efficiency aluminum sulfate treating agent with catalytic-flocculation synergistic effects. Background Art

[0002] With the acceleration of industrialization and urbanization, water pollution is becoming increasingly prominent, especially the spread of urban sewage, industrial wastewater, and pollution sources, which pose a serious threat to the environment and human health. Common water pollutants include suspended solids, heavy metals, and organic matter. Flocculation, as a cost-effective and efficient water treatment technology, plays a vital role in removing suspended particles and some soluble pollutants from water. Aluminum sulfate, a representative inorganic flocculant, is widely used in water supply and drainage treatment due to its low preparation cost, easy dosing, and excellent flocculation effect.

[0003] Although aluminum sulfate flocculants have been widely used in water treatment processes, they also have some defects in their application. The main defects include: in low-temperature or high-turbidity water bodies, the hydrolysis reaction of aluminum sulfate is slow, resulting in a decrease in flocculation efficiency; single physical adsorption and electrical neutralization effects are difficult to completely remove soluble organic matter and some difficult-to-degrade pollutants.

[0004] To overcome the shortcomings of traditional flocculants, "catalytic-flocculation synergistic treatment" has become a research hotspot in recent years. This approach introduces catalytically active components into the flocculation system to promote reactions such as the oxidative decomposition and structural transformation of pollutants, thereby enhancing the flocculent's ability to embed and adsorb pollutants. The synergistic effect of the catalytic reaction and flocculation process can significantly improve the removal rate of aluminum sulfate flocculants for complex components such as organic pollutants and heavy metal ions, while also suppressing byproduct formation and reducing treatment costs.

[0005] Chinese patent document CN106915810A discloses a high-efficiency composite flocculant, its preparation method, and application, belonging to the field of water treatment, specifically relating to a high-efficiency composite flocculant for treating papermaking wastewater. The flocculant is composed of aluminum sulfate, polyacrylamide, and polyvinyl alcohol-modified chitosan. This high-efficiency composite flocculant is effective in treating papermaking wastewater with high COD values, and the treatment effect of various indicators in the wastewater is superior to existing conventional flocculants. The COD removal rate reaches over 85%, and the turbidity and BOD removal rates are also over 78%. The light transmittance of the treated wastewater reaches over 85%. The patent uses aluminum sulfate, polyacrylamide, and polyvinyl alcohol-modified chitosan to cooperate with each other. The polyacrylamide used in the patent is difficult to completely degrade after use, and remains in the environment, causing secondary pollution problems. These residual substances may have long-term negative impacts on water bodies and soil, thereby threatening the health of ecosystems and human quality of life. Summary of the Invention

[0006] The main purpose of the present invention is to provide a high-efficiency aluminum sulfate treatment agent with catalytic-flocculation synergistic effect, which has good flocculation and degradation effects on suspended matter and organic matter in sewage.

[0007] To achieve the above object, the present invention provides a high-efficiency aluminum sulfate treating agent with catalytic-flocculating synergistic effect, comprising the following components by weight: 8-10 parts of composite catalytic-flocculating material and 10-20 parts of aluminum sulfate.

[0008] Preferably, the preparation method of the composite catalytic-flocculating material is as follows: (1) Mixing a carbon nitride precursor, ammonium bicarbonate, and water, stirring to dissolve them, removing most of the solvent by evaporation under reduced pressure, and then calcining to obtain a porous carbon nitride material; mixing bentonite with the porous carbon nitride material, adding anhydrous ethanol and stirring to mix them evenly, then adding a zinc chloride aqueous solution, and adjusting the pH value to 8-10 with a sodium hydroxide aqueous solution, and then carrying out a hydrothermal reaction in a high-pressure reactor, centrifuging, collecting the solids, washing, drying, and grinding to obtain a composite catalytic material; (2) dispersing the composite catalytic material in an ethanol aqueous solution, adding KH550, and heating the reaction to obtain a surface-treated composite catalytic material; (3) The surface treated composite catalytic material is dispersed in N,N-dimethylformamide, 4-hydroxy-3-methoxycinnamaldehyde is added, and the reaction is heated. After the reaction is completed, the solid product is filtered and dispersed in anhydrous ethanol. Dimethyldiallylammonium chloride and ammonium persulfate are added and the reaction is stirred. After the reaction is completed, the solid matter is filtered and collected. The solid matter is washed and dried to obtain a composite catalytic-flocculation material.

[0009] Preferably, the carbon nitride precursor in step S1 is at least one of cyanamide, dicyandiamide, cyanamide, urea, and thiourea; the mass ratio of the carbon nitride precursor to ammonium bicarbonate is 2-4:3-5; the calcination temperature is 400-800°C, and the calcination time is 2-4h; the mass ratio of the bentonite, porous carbon nitride material, and zinc chloride aqueous solution is 10-15:5-8:20-30; the concentration of the zinc chloride aqueous solution is 25-30wt%; the hydrothermal reaction temperature is 150-200°C, and the reaction time is 10-20h.

[0010] Preferably, in step S2, the mass ratio of the composite catalytic material to KH550 is 10-15:3-5; the heating temperature is 40-60° C., and the heating time is 4-6 hours.

[0011] Preferably, in step S3, the mass ratio of the modified composite material, 4-hydroxy-3-methoxycinnamaldehyde, and dimethyldiallylammonium chloride is 8-12:3-5:6-10; the heating temperature is 30-50° C., and the heating time is 3-5 hours; the stirring reaction temperature is 20-30° C., and the reaction time is 15-18 hours.

[0012] The composite catalytic-flocculating material of the present invention uses a composite catalytic material as a base material, is surface-treated with KH550, and amino groups are introduced on the surface of the composite catalytic material. The amino groups react with 4-hydroxy-3-methoxycinnamaldehyde to generate a Schiff base and introduce a double bond. Finally, dimethyldiallylammonium chloride undergoes a polymerization reaction with the carbon-carbon double bond under the action of ammonium persulfate, and a cationic compound dimethyldiallylammonium chloride is grafted onto the surface of the composite catalytic material to obtain the composite catalytic-flocculating material.

[0013] The invention also discloses a preparation method of the catalytic-flocculating synergistic efficient aluminum sulfate treating agent, comprising the following steps: stirring and uniformly mixing a composite catalytic-flocculating material and aluminum sulfate to obtain the catalytic-flocculating synergistic efficient aluminum sulfate treating agent.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention provides a high-efficiency aluminum sulfate treatment agent with catalytic-flocculation synergistic effects and a preparation method thereof, which solves the problems of limited efficiency and narrow application range of traditional single flocculants in wastewater treatment. Through the synergistic effect of organic and inorganic flocculants and the introduction of composite materials with photocatalytic and flocculation properties, the removal efficiency of suspended matter, heavy metal ions, and organic matter in water bodies is effectively improved, achieving synergistic treatment of multiple pollutants. The treatment agent has a simple preparation process, mild process conditions, low cost, good environmental and economic benefits, and is suitable for the purification and treatment of industrial wastewater, municipal sewage, and complex water bodies. 2. The composite catalytic-flocculating material of the present invention is based on a composite catalytic material. The composite catalytic material is prepared by introducing nano-sized zinc oxide into a porous carbon nitride material to form a highly hybridized nanocomposite system, which is then uniformly loaded on a bentonite matrix. This not only significantly increases the specific surface area of ​​the composite material but also broadens the material's response range to visible light. The composite catalytic-flocculating material not only generates a large number of active free radicals under light conditions, promoting the decomposition of organic pollutants, but also achieves efficient adsorption and flocculation of pollutants through surface active groups, significantly improving the ability to remove organic matter and heavy metal ions in water. 3. The Schiff base, hydroxyl group and imidazole group in the composite catalytic-flocculating material of the present invention can provide more adsorption and coordination sites, can coordinate with metal ions in sewage, and then remove the metal ions, and the positive charge in the cationic flocculant can neutralize the negative charge on the surface of the colloidal particles, reduce the electrostatic repulsion between the particles, and promote the aggregation of the particles; on the other hand, the cationic compound dimethyldiallyl ammonium chloride can be adsorbed on the surfaces of multiple particles at the same time, and can connect multiple particles together through a bridging effect to form larger flocs, which is convenient for precipitation and separation, thereby achieving the flocculation effect. Compared with ordinary physical mixing, the connection between 4-hydroxy-3-methoxycinnamaldehyde, dimethyldiallyl ammonium chloride and the composite catalytic material is tighter, so that the high-efficiency aluminum sulfate treatment agent with synergistic catalytic-flocculating effect is not easily lost with the water flow in the continuous flow system, thereby improving the utilization rate of the material. DETAILED DESCRIPTION

[0015] To avoid redundancy, the items used in the following examples are all commercially available products unless otherwise specified, 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: Bentonite, 200-260 mesh, was purchased from Qingdao Ruihexiang Refractory Materials Co., Ltd.

[0017] Example 1 A method for preparing a high-efficiency aluminum sulfate treating agent with catalytic-flocculation synergistic effect comprises the following steps: (1) 30 g of dicyandiamide, 40 g of ammonium bicarbonate, and 100 mL of water were mixed and stirred to dissolve, 80% of the solvent was removed by evaporation under reduced pressure, and then the mixture was placed in a muffle furnace and calcined at 550 ° C for 3 h to obtain a porous carbon nitride material; 24 g of bentonite was mixed with 14 g of porous carbon nitride material, 200 mL of anhydrous ethanol was added and stirred thoroughly to mix evenly, and then 500 g of a 28 wt% zinc chloride aqueous solution was added, and the pH value was adjusted to 9 with a 1 mol / L sodium hydroxide aqueous solution, and then a hydrothermal reaction was carried out in a high-pressure reactor at a hydrothermal reaction temperature of 180 ° C and a hydrothermal reaction time of 12 h. After the reaction was completed, the mixture was cooled, centrifuged, and the solid matter was collected, washed, dried, and ground to obtain a composite catalytic material; (2) Disperse 23 g of the composite catalytic material in 200 mL of 50 wt% ethanol aqueous solution, add 7.8 g of KH550, and heat the reaction at 50 °C for 5 h. After the reaction is completed, filter and collect the solid product, wash and dry to obtain the surface-treated composite catalytic material; (3) Disperse 10 g of the surface-treated composite catalytic material in 200 mL of N,N-dimethylformamide, add 4.5 g of 4-hydroxy-3-methoxycinnamaldehyde, and heat the mixture at 40 °C for 4 h. After the reaction is completed, filter the mixture, disperse the solid product in 200 mL of anhydrous ethanol, add 8 g of dimethyldiallylammonium chloride and 0.8 g of ammonium persulfate, and stir the mixture at 25 °C for 16 h. After the reaction is completed, filter the solid matter, and wash and dry the solid matter to obtain a composite catalytic-flocculation material. (4) 9 g of the composite catalytic-flocculating material and 15 g of aluminum sulfate were evenly mixed to obtain the high-efficiency aluminum sulfate treatment agent with catalytic-flocculating synergistic effect.

[0018] Example 2 A method for preparing a high-efficiency aluminum sulfate treating agent with catalytic-flocculation synergistic effect comprises the following steps: (1) 20 g of dicyandiamide, 30 g of ammonium bicarbonate, and 100 mL of water were mixed and stirred to dissolve, 80% of the solvent was removed by evaporation under reduced pressure, and then the mixture was placed in a muffle furnace and calcined at 550 ° C for 3 h to obtain a porous carbon nitride material; 20 g of bentonite was mixed with 10 g of the porous carbon nitride material, 200 mL of anhydrous ethanol was added and stirred thoroughly to mix evenly, and then 400 g of a 25 wt% zinc chloride aqueous solution was added, and the pH value was adjusted to 8 with a 1 mol / L sodium hydroxide aqueous solution, and then a hydrothermal reaction was carried out in a high-pressure reactor at a hydrothermal reaction temperature of 180 ° C and a hydrothermal reaction time of 12 h. After the reaction was completed, the mixture was cooled, centrifuged, and the solid matter was collected, washed, dried, and ground to obtain a composite catalytic material; (2) Disperse 20 g of the composite catalytic material in 200 mL of 50 wt% ethanol aqueous solution, add 6 g of KH550, and heat the reaction at 40 °C for 6 h. After the reaction is completed, filter and collect the solid product, wash and dry it to obtain the surface-treated composite catalytic material; (3) 8 g of the surface-treated composite catalytic material was dispersed in 200 mL of N,N-dimethylformamide, 3 g of 4-hydroxy-3-methoxycinnamaldehyde was added, and the mixture was heated at 30 °C for 5 h. After the reaction was completed, the mixture was filtered and the solid product was dispersed in 200 mL of anhydrous ethanol. 6 g of dimethyldiallylammonium chloride and 0.6 g of ammonium persulfate were added and the mixture was stirred at 20 °C for 18 h. After the reaction was completed, the solid matter was collected by filtration and washed and dried to obtain a composite catalytic-flocculation material. (4) 8 g of the composite catalytic-flocculating material and 10 g of aluminum sulfate were evenly mixed to obtain the high-efficiency aluminum sulfate treatment agent with catalytic-flocculating synergistic effect.

[0019] Example 3 A method for preparing a high-efficiency aluminum sulfate treating agent with catalytic-flocculation synergistic effect comprises the following steps: (1) 40 g of dicyandiamide, 50 g of ammonium bicarbonate, and 200 mL of water were mixed and stirred to dissolve, 80% of the solvent was removed by evaporation under reduced pressure, and then the mixture was placed in a muffle furnace and calcined at 550 ° C for 3 h to obtain a porous carbon nitride material; 30 g of bentonite was mixed with 16 g of porous carbon nitride material, 200 mL of anhydrous ethanol was added and stirred thoroughly to mix evenly, and then 600 g of a 30 wt% zinc chloride aqueous solution was added, and the pH value was adjusted to 10 with a 1 mol / L sodium hydroxide aqueous solution, and then a hydrothermal reaction was carried out in a high-pressure reactor at a hydrothermal reaction temperature of 180 ° C and a hydrothermal reaction time of 12 h. After the reaction was completed, the mixture was cooled, centrifuged, and the solid matter was collected, washed, dried, and ground to obtain a composite catalytic material; (2) Disperse 30 g of the composite catalytic material in 200 mL of 50 wt% ethanol aqueous solution, add 10 g of KH550, and heat the reaction at 60 °C for 4 h. After the reaction is completed, filter and collect the solid product, wash and dry to obtain the surface-treated composite catalytic material; (3) 12 g of the surface-treated composite catalytic material was dispersed in 200 mL of N,N-dimethylformamide, 5 g of 4-hydroxy-3-methoxycinnamaldehyde was added, and the mixture was heated at 50 °C for 3 h. After the reaction was completed, the mixture was filtered and the solid product was dispersed in 200 mL of anhydrous ethanol. 10 g of dimethyldiallylammonium chloride and 1 g of ammonium persulfate were added, and the mixture was stirred at 30 °C for 15 h. After the reaction was completed, the solid matter was collected by filtration, and the solid matter was washed and dried to obtain a composite catalytic-flocculation material. (4) 10 g of the composite catalytic-flocculating material and 20 g of aluminum sulfate were mixed evenly to obtain the high-efficiency aluminum sulfate treating agent with catalytic-flocculating synergistic effect.

[0020] Comparative Example 1 A method for preparing a high-efficiency aluminum sulfate treating agent with catalytic-flocculating synergistic effects is similar to Example 1, except that polydimethyldiallylammonium chloride is not grafted, and specifically comprises the following steps: (1) 30 g of dicyandiamide, 40 g of ammonium bicarbonate, and 100 mL of water were mixed and stirred to dissolve, 80% of the solvent was removed by evaporation under reduced pressure, and then the mixture was placed in a muffle furnace and calcined at 550 ° C for 3 h to obtain a porous carbon nitride material; 24 g of bentonite was mixed with 14 g of porous carbon nitride material, 200 mL of anhydrous ethanol was added and stirred thoroughly to mix evenly, and then 500 g of a 28 wt% zinc chloride aqueous solution was added, and the pH value was adjusted to 9 with a 1 mol / L sodium hydroxide aqueous solution, and then a hydrothermal reaction was carried out in a high-pressure reactor at a hydrothermal reaction temperature of 180 ° C and a hydrothermal reaction time of 12 h. After the reaction was completed, the mixture was cooled, centrifuged, and the solid matter was collected, washed, dried, and ground to obtain a composite catalytic material; (2) Disperse 23 g of the composite catalytic material in 200 mL of 50 wt% ethanol aqueous solution, add 7.8 g of KH550, and heat the reaction at 50 °C for 5 h. After the reaction is completed, filter and collect the solid product, wash and dry to obtain the surface-treated composite catalytic material; (3) Disperse 10 g of the surface-treated composite catalytic material in 200 mL of N,N-dimethylformamide, add 4.5 g of 4-hydroxy-3-methoxycinnamaldehyde, and heat at 40 °C for 4 h. After the reaction is completed, filter, wash, and dry the solid product to obtain a composite catalytic-flocculation material; (4) 9 g of the composite catalytic-flocculating material and 15 g of aluminum sulfate were evenly mixed to obtain the high-efficiency aluminum sulfate treatment agent with catalytic-flocculating synergistic effect.

[0021] Comparative Example 2 A method for preparing a high-efficiency aluminum sulfate treating agent is similar to that of Example 1, except that the composite catalytic-flocculating material is a mixture of the composite catalytic material and dimethyldiallylammonium chloride, and comprises the following steps: (1) 30 g of dicyandiamide, 40 g of ammonium bicarbonate, and 100 mL of water were mixed and stirred to dissolve, 80% of the solvent was removed by evaporation under reduced pressure, and then the mixture was placed in a muffle furnace and calcined at 550 ° C for 3 h to obtain a porous carbon nitride material; 24 g of bentonite was mixed with 14 g of porous carbon nitride material, 200 mL of anhydrous ethanol was added and stirred thoroughly to mix evenly, and then 500 g of a 28 wt% zinc chloride aqueous solution was added, and the pH value was adjusted to 9 with a 1 mol / L sodium hydroxide aqueous solution, and then a hydrothermal reaction was carried out in a high-pressure reactor at a hydrothermal reaction temperature of 180 ° C and a hydrothermal reaction time of 12 h. After the reaction was completed, the mixture was cooled, centrifuged, and the solid matter was collected, washed, dried, and ground to obtain a composite catalytic material; (2) Disperse 23 g of the composite catalytic material in 200 mL of 50 wt% ethanol aqueous solution, add 7.8 g of KH550, and heat the reaction at 50 °C for 5 h. After the reaction is completed, filter and collect the solid product, wash and dry to obtain the surface-treated composite catalytic material; (3) 10 g of the surface-treated composite catalytic material, 4.5 g of 4-hydroxy-3-methoxycinnamaldehyde, and 8 g of dimethyldiallylammonium chloride were mixed and stirred to obtain a composite catalytic-flocculating material; (4) 9 g of the composite catalytic-flocculating material and 15 g of aluminum sulfate were mixed evenly to obtain the high-efficiency aluminum sulfate treatment agent.

[0022] Performance Testing Taking the printing and dyeing wastewater of a certain factory as the object, the high-efficiency aluminum sulfate treatment agent prepared in Examples 1-3 and Comparative Examples 1-2 was used to conduct a flocculation effect test on the printing and dyeing wastewater. The test was carried out simultaneously in 5 sedimentation tanks, and the dosage of the high-efficiency aluminum sulfate treatment agent was 1 g / L. After stirring, it was allowed to stand for 1 hour and irradiated under ultraviolet light for 3 hours. The chemical oxygen demand, suspended solids, decolorization rate, heavy metal ion removal rate and other parameters of the sewage before and after the addition of the flocculant were measured; the determination of COD (chemical oxygen demand) referred to HJ828-2017 "Water Quality Determination of Chemical Oxygen Demand Dichromate Method", and the determination of SS (suspended solids) referred to GB11901-1989 "Water Quality Determination of Suspended Solids Gravimetric Method", and the decolorization rate was determined by UV-visible spectrophotometry. The test results are shown in Table 1: Table 1 Flocculation performance test results of high-efficiency aluminum sulfate treatment agent It can be seen from the experimental results in Table 1 that the high-efficiency aluminum sulfate treating agent with catalytic-flocculation synergistic effect prepared by the present invention has a good sewage treatment effect.

[0023] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of the present invention.

Claims

1. A high-efficiency aluminum sulfate treating agent with catalytic-flocculating synergistic effect, characterized in that: The invention comprises the following components in parts by mass: 8-10 parts of composite catalytic-flocculating material and 10-20 parts of aluminum sulfate.

2. The high-efficiency aluminum sulfate treating agent according to claim 1, wherein The preparation method of the composite catalytic-flocculating material is as follows: (1) Mixing a carbon nitride precursor, ammonium bicarbonate, and water, stirring to dissolve them, removing most of the solvent by vacuum distillation, and then calcining to obtain a porous carbon nitride material; mixing bentonite with the porous carbon nitride material, adding anhydrous ethanol and stirring to mix them evenly, then adding a zinc chloride aqueous solution, and adjusting the pH value to 8-10 with a sodium hydroxide aqueous solution, and then performing a hydrothermal reaction in a high-pressure reactor, centrifuging, collecting the solids, washing, drying, and grinding to obtain a composite catalytic material; (2) dispersing the composite catalytic material in an ethanol aqueous solution, adding KH550, and heating the reaction to obtain a surface-treated composite catalytic material; (3) The surface treated composite catalytic material is dispersed in N,N-dimethylformamide, 4-hydroxy-3-methoxycinnamaldehyde is added, and the reaction is heated. After the reaction is completed, the solid product is filtered and dispersed in anhydrous ethanol. Dimethyldiallylammonium chloride and ammonium persulfate are added and the reaction is stirred. After the reaction is completed, the solid matter is filtered and collected. The solid matter is washed and dried to obtain a composite catalytic-flocculation material.

3. The high-efficiency aluminum sulfate treating agent according to claim 2, wherein: In step S1, the carbon nitride precursor is at least one of cyanamide, dicyandiamide, cyanamide, urea, and thiourea.

4. The high-efficiency aluminum sulfate treating agent according to claim 2, wherein: In step S1, the mass ratio of the carbon nitride precursor to ammonium bicarbonate is 2-4:3-5.

5. The high-efficiency aluminum sulfate treating agent according to claim 2, wherein: In step S1, the mass ratio of bentonite, porous carbon nitride material, and zinc chloride aqueous solution is 10-15:5-8:20-30; and the concentration of the zinc chloride aqueous solution is 25-30 wt%.

6. The high-efficiency aluminum sulfate treating agent according to claim 2, characterized in that: The hydrothermal reaction temperature is 150-200° C., and the reaction time is 10-20 hours.

7. The high-efficiency aluminum sulfate treating agent according to claim 2, wherein: In step S2, the mass ratio of the composite catalytic material to KH550 is 10-15:3-5; the heating temperature is 40-60° C., and the heating time is 4-6 hours.

8. The high-efficiency aluminum sulfate treating agent according to claim 2, wherein: In step S3, the mass ratio of the modified composite material, 4-hydroxy-3-methoxycinnamaldehyde, and dimethyldiallylammonium chloride is 8-12:3-5:6-10.

9. The high-efficiency aluminum sulfate treating agent according to claim 2, wherein: In step S3, the heating temperature is 30-50° C. and the heating time is 3-5 hours; the stirring reaction temperature is 20-30° C. and the reaction time is 15-18 hours.

10. A method for preparing the high-efficiency aluminum sulfate treating agent according to any one of claims 1 to 9, characterized in that: The composite catalytic-flocculating material and aluminum sulfate are stirred and mixed evenly to obtain a high-efficiency aluminum sulfate treating agent with catalytic-flocculating synergistic effects.

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