Preparation and application of a modified chitosan adsorption ball

Abstract

This invention relates to the field of water pollution control technology and discloses the preparation and application of modified chitosan adsorption balls. The invention involves grafting modified nano-micron high-purity composite active iron onto chitosan, then mixing it with dried and crushed sludge. The modified nano-micron high-purity composite active iron is then reacted with the chitosan to modify it. First, the surface of the nano-micron high-purity composite active iron is made to have active functional groups, and then it reacts with chitosan. At this point, the chitosan also has a dispersing effect, resulting in better performance and achieving a synergistic effect of dual phosphorus removal. This invention has low cost, simple operation, and good economic benefits.

Description

Technical Field

[0001] This invention relates to the field of water pollution control technology, specifically to the preparation and application of a modified chitosan adsorption ball. Background Technology

[0002] Water pollution mainly includes domestic wastewater and industrial wastewater. Industrial wastewater has a complex composition, including organophosphorus wastewater, heavy metal wastewater, dyeing and printing wastewater, and radioactive wastewater. Among them, dyeing and printing wastewater is the most representative. It has high acidity and alkalinity, high dye concentration, complex and variable composition, and contains a lot of salt and carcinogenic aromatic hydrocarbons. Commonly used treatment methods for dyeing and printing wastewater include adsorption, biodegradation, and chemical methods. Among them, adsorption is able to remove pollutants quickly and easily, is low in cost, and is easy to operate.

[0003] Chitosan is a natural macromolecular polysaccharide. Chitosan and its derivatives have good biocompatibility, are biodegradable, and contain abundant hydroxyl and amino groups, exhibiting good adsorption properties for heavy metals. Patent CN111013548B discloses a method for preparing zirconium-modified chitosan microspheres and their application. Chitosan microspheres are prepared at room temperature, and then zirconium ions are loaded onto the surface of the chitosan microspheres to obtain zirconium-modified chitosan microspheres with good adsorption effects. This invention obtains a highly efficient adsorbent for treating phosphorus-containing wastewater by modifying nano- and micro-sized high-purity composite active iron grafted onto chitosan. Summary of the Invention

[0004] (a) Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this invention provides a method for preparing and applying modified chitosan adsorption spheres, which exhibit excellent adsorption capacity and good phosphorus removal effect on wastewater.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, the present invention provides the following technical solution: a modified chitosan adsorption ball, wherein the modified chitosan adsorption ball is prepared according to the following steps: 20-30g of modified nano-micro high-purity composite active iron-grafted chitosan and 10-20g of dried and crushed sludge are added to a reactor and stirred and mixed, and stirred at 30-50℃ for 2-6h to obtain the modified chitosan adsorption ball.

[0008] Preferably, the mass ratio of the modified nano-micro high-purity composite active iron-grafted chitosan to the dried and crushed sludge is 1.5-2:1.

[0009] Preferably, the modified nano-micro high-purity composite active iron-grafted chitosan is prepared according to the following steps:

[0010] (1) Add 10-15g of nano-micro high-purity composite active iron and 10-12g of 3-(methacryloyloxy)propyltrimethoxysilane to ethanol solvent and ultrasonically disperse at 30-60℃ for 2-3h to obtain methacrylic acid modified nano-micro high-purity composite active iron.

[0011] (2) Add methpropylene-modified nano-micro high-purity composite active iron to N,N-dimethylformamide solvent for dissolution. After dissolution, add diallyl dimethylammonium chloride and catalyst dibutyltin dilaurate. React at 40-80℃ for 4-8h. After the reaction, wash with anhydrous ethanol and deionized water, filter and dry to obtain quaternized ammonium-modified nano-micro high-purity composite active iron.

[0012] (3) Add 2-3g of quaternized ammonium modified nano-micro high-purity composite active iron and 1-2g of epoxy agent to toluene solvent, react at 60-100℃ for 2-6h, filter, wash and dry to obtain epoxidized modified nano-micro high-purity composite active iron.

[0013] (4) Add 2-4g of chitosan to acetic acid solvent to dissolve it. After dissolution, add 1-3g of epoxidized modified nano-micro high-purity composite active iron under constant pressure and carry out water bath reaction. After the reaction is completed, distill under reduced pressure, wash with anhydrous ethanol, filter and dry to obtain modified nano-micro high-purity composite active iron.

[0014] Preferably, in (2), the mass ratio of methacrylate-modified nano-micro high-purity composite active iron, diallyl dimethyl ammonium chloride, and dibutyltin dilaurate is 3-4:1:0.01-0.02.

[0015] Preferably, the epoxy agent in (3) is hydrogen peroxide, peracetic acid, or benzoyl peroxide.

[0016] Preferably, the water bath reaction temperature in (4) is 60-90℃ and the reaction time is 2-6h.

[0017] Preferably, the modified chitosan adsorbent spheres are used in the treatment of phosphorus-containing wastewater.

[0018] (III) Beneficial Technical Effects

[0019] This invention involves grafting chitosan onto modified nano-micron high-purity composite activated iron, then mixing it with dried and crushed sludge. The nano-micron inorganic material has a high specific surface area. The modified nano-micron high-purity composite activated iron is then grafted onto chitosan, modifying the chitosan. First, the surface of the nano-micron high-purity composite activated iron is made to have active functional groups, and then it reacts with chitosan. At this point, the chitosan also has a dispersing effect, resulting in better performance and a synergistic effect of dual phosphorus removal. The quaternary ammonium salt groups in the modified nano-micron high-purity composite activated iron also have a good adsorption effect on phosphorus, synergistically treating phosphorus-containing wastewater. This invention has low cost, simple operation process, and good economic benefits. Attached Figure Description

[0020] Figure 1 It is a reaction formula for modified nano-micro high-purity composite active iron grafted chitosan.

[0021] Figure 2 It represents the adsorption capacity of modified chitosan adsorption balls for phosphorus-containing wastewater. Detailed Implementation

[0022] Example 1

[0023] (1) 10g of nano-micro high-purity composite active iron and 10g of 3-(methacryloyloxy)propyltrimethoxysilane were added to ethanol solvent and ultrasonically dispersed at 30°C for 2h to obtain methacrylic acid modified nano-micro high-purity composite active iron.

[0024] (2) 6g of methpropylene-modified nano-micro high-purity composite active iron was added to N,N-dimethylformamide solvent for dissolution. After dissolution, 3g of diallyl dimethyl ammonium chloride and 0.01g of catalyst dibutyltin dilaurate were added. The reaction was carried out at 40℃ for 4h. After the reaction was completed, the mixture was washed with anhydrous ethanol and deionized water, filtered and dried to obtain quaternized ammonium-modified nano-micro high-purity composite active iron.

[0025] (3) Add 2g of quaternized ammonium modified nano-micro high-purity composite active iron and 1g of epoxy agent benzoyl peroxide to toluene solvent, react at 60℃ for 2h, filter, wash and dry to obtain epoxidized modified nano-micro high-purity composite active iron.

[0026] (4) Add 2g of chitosan to acetic acid solvent to dissolve it. After dissolution, add 1g of epoxidized modified nano-micro high-purity composite active iron under constant pressure. Carry out the reaction in a water bath at 60℃ for 2h. After the reaction, distill under reduced pressure, wash with anhydrous ethanol, filter and dry to obtain modified nano-micro high-purity composite active iron.

[0027] (5) Add 20g of modified nano-micro high-purity composite active iron-grafted chitosan and 10g of dried and crushed sludge to the reactor and stir and mix them. Stir at 30°C for 2h to obtain modified chitosan adsorption balls.

[0028] Example 2

[0029] (1) 15g of nano-micro high-purity composite active iron and 12g of 3-(methacryloyloxy)propyltrimethoxysilane were added to ethanol solvent and ultrasonically dispersed at 60℃ for 3h to obtain methacrylic acid modified nano-micro high-purity composite active iron.

[0030] (2) Add 8g of methpropylene-modified nano-micro high-purity composite active iron to N,N-dimethylformamide solvent for dissolution. After dissolution, add 4g of diallyl dimethyl ammonium chloride and 0.02g of catalyst dibutyltin dilaurate. React at 80℃ for 8h. After the reaction, wash with anhydrous ethanol and deionized water, filter and dry to obtain quaternized ammonium-modified nano-micro high-purity composite active iron.

[0031] (3) Add 3g of quaternized ammonium modified nano-micro high-purity composite active iron and 2g of epoxy agent benzoyl peroxide to toluene solvent, react at 100℃ for 6h, filter, wash and dry to obtain epoxidized modified nano-micro high-purity composite active iron.

[0032] (4) Add 4g of chitosan to acetic acid solvent to dissolve it. After dissolution, add 3g of epoxidized modified nano-micro high-purity composite active iron under constant pressure. The reaction is carried out in a water bath at 90℃ for 6 hours. After the reaction is completed, the mixture is distilled under reduced pressure, washed with anhydrous ethanol, filtered and dried to obtain modified nano-micro high-purity composite active iron.

[0033] (5) Add 30g of modified nano-micro high-purity composite active iron-grafted chitosan and 20g of dried and crushed sludge to the reactor and stir and mix them. Stir at 50°C for 6h to obtain modified chitosan adsorption balls.

[0034] Example 3

[0035] (1) 12.5g of nano-micro high-purity composite active iron and 11g of 3-(methacryloyloxy)propyltrimethoxysilane were added to ethanol solvent and ultrasonically dispersed at 45℃ for 2.5h to obtain methacrylic modified nano-micro high-purity composite active iron.

[0036] (2) 7g of methpropylene-modified nano-micro high-purity composite active iron was added to N,N-dimethylformamide solvent for dissolution. After dissolution, 3.5g of diallyl dimethylammonium chloride and 0.015g of catalyst dibutyltin dilaurate were added. The reaction was carried out at 60℃ for 6h. After the reaction was completed, the mixture was washed with anhydrous ethanol and deionized water, filtered and dried to obtain quaternized ammonium-modified nano-micro high-purity composite active iron.

[0037] (3) Add 2.5g of quaternized ammonium modified nano-micro high-purity composite active iron and 1.5g of epoxy agent benzoyl peroxide to toluene solvent, react at 80℃ for 4h, filter, wash and dry to obtain epoxidized modified nano-micro high-purity composite active iron.

[0038] (4) Add 3g of chitosan to acetic acid solvent to dissolve it. After dissolution, add 2g of epoxidized modified nano-micro high-purity composite active iron under constant pressure. The reaction is carried out in a water bath at 75°C for 4 hours. After the reaction is completed, the mixture is distilled under reduced pressure, washed with anhydrous ethanol, filtered and dried to obtain modified nano-micro high-purity composite active iron.

[0039] (5) Add 25g of modified nano-micro high-purity composite active iron-grafted chitosan and 15g of dried and crushed sludge to the reactor and stir and mix them. Stir at 40°C for 4 hours to obtain modified chitosan adsorption balls.

[0040] Example 4

[0041] (1) 10g of nano-micro high-purity composite active iron and 10g of 3-(methacryloyloxy)propyltrimethoxysilane were added to ethanol solvent and ultrasonically dispersed at 30°C for 2h to obtain methacrylic acid modified nano-micro high-purity composite active iron.

[0042] (2) 6g of methpropylene-modified nano-micro high-purity composite active iron was added to N,N-dimethylformamide solvent for dissolution. After dissolution, 3g of diallyl dimethyl ammonium chloride and 0.01g of catalyst dibutyltin dilaurate were added. The reaction was carried out at 40℃ for 4h. After the reaction was completed, the mixture was washed with anhydrous ethanol and deionized water, filtered and dried to obtain quaternized ammonium-modified nano-micro high-purity composite active iron.

[0043] (3) Add 3g of quaternized ammonium modified nano-micro high-purity composite active iron and 2g of epoxy agent benzoyl peroxide to toluene solvent, react at 100℃ for 6h, filter, wash and dry to obtain epoxidized modified nano-micro high-purity composite active iron.

[0044] (4) Add 4g of chitosan to acetic acid solvent to dissolve it. After dissolution, add 3g of epoxidized modified nano-micro high-purity composite active iron under constant pressure. The reaction is carried out in a water bath at 90℃ for 6 hours. After the reaction is completed, the mixture is distilled under reduced pressure, washed with anhydrous ethanol, filtered and dried to obtain modified nano-micro high-purity composite active iron.

[0045] (5) Add 25g of modified nano-micro high-purity composite active iron-grafted chitosan and 15g of dried and crushed sludge to the reactor and stir and mix them. Stir at 40°C for 4 hours to obtain modified chitosan adsorption balls.

[0046] Example 5

[0047] (1) 15g of nano-micro high-purity composite active iron and 12g of 3-(methacryloyloxy)propyltrimethoxysilane were added to ethanol solvent and ultrasonically dispersed at 60℃ for 3h to obtain methacrylic acid modified nano-micro high-purity composite active iron.

[0048] (2) Add 8g of methpropylene-modified nano-micro high-purity composite active iron to N,N-dimethylformamide solvent for dissolution. After dissolution, add 4g of diallyl dimethyl ammonium chloride and 0.02g of catalyst dibutyltin dilaurate. React at 80℃ for 8h. After the reaction, wash with anhydrous ethanol and deionized water, filter and dry to obtain quaternized ammonium-modified nano-micro high-purity composite active iron.

[0049] (3) Add 2.5g of quaternized ammonium modified nano-micro high-purity composite active iron and 1.5g of epoxy agent benzoyl peroxide to toluene solvent, react at 80℃ for 4h, filter, wash and dry to obtain epoxidized modified nano-micro high-purity composite active iron.

[0050] (4) Add 3g of chitosan to acetic acid solvent to dissolve it. After dissolution, add 2g of epoxidized modified nano-micro high-purity composite active iron under constant pressure. The reaction is carried out in a water bath at 75°C for 4 hours. After the reaction is completed, the mixture is distilled under reduced pressure, washed with anhydrous ethanol, filtered and dried to obtain modified nano-micro high-purity composite active iron.

[0051] (5) Add 20g of modified nano-micro high-purity composite active iron-grafted chitosan and 10g of dried and crushed sludge to the reactor and stir and mix them. Stir at 30°C for 2h to obtain modified chitosan adsorption balls.

[0052] Comparative Example 1

[0053] (1) 12.5g of nano-micro high-purity composite active iron and 11g of 3-(methacryloyloxy)propyltrimethoxysilane were added to ethanol solvent and ultrasonically dispersed at 45℃ for 2.5h to obtain methacrylic modified nano-micro high-purity composite active iron.

[0054] (2) 7g of methpropylene-modified nano-micro high-purity composite active iron was added to N,N-dimethylformamide solvent for dissolution. After dissolution, 3.5g of diallyl dimethylammonium chloride and 0.015g of catalyst dibutyltin dilaurate were added. The reaction was carried out at 60℃ for 6h. After the reaction was completed, the mixture was washed with anhydrous ethanol and deionized water, filtered and dried to obtain quaternized ammonium-modified nano-micro high-purity composite active iron.

[0055] (3) Add 2g of quaternized ammonium modified nano-micro high-purity composite active iron and 1g of epoxy agent benzoyl peroxide to toluene solvent, react at 60℃ for 2h, filter, wash and dry to obtain epoxidized modified nano-micro high-purity composite active iron.

[0056] (4) Add 4g of chitosan to acetic acid solvent to dissolve it. After dissolution, add 3g of epoxidized modified nano-micro high-purity composite active iron under constant pressure. The reaction is carried out in a water bath at 90℃ for 6 hours. After the reaction is completed, the mixture is distilled under reduced pressure, washed with anhydrous ethanol, filtered and dried to obtain modified nano-micro high-purity composite active iron.

[0057] (5) Add 30g of modified nano-micro high-purity composite active iron-grafted chitosan and 20g of dried and crushed sludge to the reactor and stir and mix them. Stir at 50°C for 6h to obtain modified chitosan adsorption balls.

[0058] Comparative Example 2

[0059] (5) Add 30g of nano-micro high-purity composite active iron and 20g of dried and crushed sludge to the reactor and stir and mix them. Stir at 50°C for 6 hours to obtain adsorption balls.

[0060] Phosphorus-containing wastewater was selected for adsorption experiments. During the experiment, its concentration was detected using a UV spectrophotometer. Adsorption capacity versus time curves were plotted based on known gradient concentrations of phosphorus-containing wastewater solutions. Measurements were taken every 40 min, 100 min, and 150 min. The test results are as follows: Figure 1 .

[0061] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A modified chitosan adsorbent sphere, characterized in that, The modified chitosan adsorption spheres are prepared according to the following steps: Modified nano-micro high-purity composite active iron-grafted chitosan and dried and crushed sludge are added to a reactor and stirred and mixed. The mixture is stirred at 30-50℃ for 2-6 hours to obtain modified chitosan adsorption spheres. The modified nano-micro high-purity composite active iron-grafted chitosan was prepared according to the following steps: (1) Add 10-15g of nano-micro high-purity composite active iron and 10-12g of 3-(methacryloyloxy)propyltrimethoxysilane to ethanol solvent and ultrasonically disperse at 30-60℃ for 2-3h to obtain methacrylic acid modified nano-micro high-purity composite active iron. (2) Add methacrylate-modified nano-micro high-purity composite active iron to N,N-dimethylformamide solvent for dissolution. After dissolution, add diallyl dimethylammonium chloride and catalyst dibutyltin dilaurate. React at 40-80℃ for 4-8h. After the reaction, wash with anhydrous ethanol and deionized water, filter and dry to obtain quaternized ammonium-modified nano-micro high-purity composite active iron. (3) Add 2-3g of quaternized ammonium modified nano-micro high-purity composite active iron and 1-2g of epoxy agent to toluene solvent, react at 60-100℃ for 2-6h, filter, wash and dry to obtain epoxidized modified nano-micro high-purity composite active iron. (4) Add 2-4g of chitosan to acetic acid solvent to dissolve it. After dissolution, add 1-3g of epoxidized modified nano-micron high-purity composite active iron under constant pressure and carry out water bath reaction. After the reaction is completed, distill under reduced pressure, wash with anhydrous ethanol, filter and dry to obtain modified nano-micron high-purity composite active iron grafted chitosan.

2. The modified chitosan adsorbent sphere according to claim 1, characterized in that, The mass ratio of the modified nano-micro high-purity composite active iron-grafted chitosan to the dried and crushed sludge is 1.5-2:

1.

3. The modified chitosan adsorbent sphere according to claim 1, characterized in that, In (2), the mass ratio of methpropylene-modified nano-micron high-purity composite active iron, diallyl dimethyl ammonium chloride, and dibutyltin dilaurate is 3-4:1:0.01-0.

02.

4. The modified chitosan adsorbent sphere according to claim 1, characterized in that, The epoxy agent in (3) is hydrogen peroxide, peracetic acid, or benzoyl peroxide.

5. The modified chitosan adsorbent sphere according to claim 1, characterized in that, The water bath reaction temperature in (4) is 60-90℃, and the reaction time is 2-6h.

6. The application of the modified chitosan adsorbent spheres as described in any one of claims 1-5 in the treatment of phosphorus-containing wastewater.

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