Preparation method of macroporous strong-alkaline anion exchange resin for removing nitrate in water

Abstract

The invention discloses a preparation method of styrene macroporous strong-alkaline anion exchange resin for removing nitrate in water. Styrene, divinyl benzene, benzoyl peroxide, liquid paraffin, polyvinyl alcohol, gelatin, methylene blue, dichloromethane, 1,4-bis(chloromethoxy)butane, anhydrous tin tetrachloride and triethylamine are used as main raw materials; the macroporous strong-alkaline anion exchange resin is prepared through suspension polymerization reaction, chloromethylation reaction and amination reaction. The preparation comprises the following steps: synthesis of styrene divinyl benzene cross-linked polymer by the suspension polymerization method, chloromethylation reaction of styrene divinyl benzene cross-linked polymer, and amination reaction of chloromethylated styrene divinyl benzene cross-linked polymer. The particle size of the prepared resin is 0.5-1.5mm; the resin has the advantages of uniform pore distribution, strong adsorbability against nitrate, high selectivity on nitrate and the like; the physicochemical properties of the resin are good. The resin can be applied to the nitrate removal treatment process of water, and has good development prospect and practical significance.

Description

technical field

[0001] The invention belongs to the preparation process of ion exchange resins, in particular to a preparation method of macroporous strongly basic styrene-based anion exchange resins for removing nitrate in water. Background technique

[0002] After nitrate enters the human body, it is easily reduced to nitrite and causes methemoglobinemia, and it also has the risk of causing cancer in the human body. In addition, nitrogen is one of the important nutrient sources that cause eutrophication of water bodies. Therefore, how to remove nitrogen in water cost-effectively has always been one of the current engineering problems in water quality security and water environment protection. At present, the main methods for treating wastewater polluted by nitrates are: ion exchange, biological denitrification, chemical reduction, reverse osmosis and electrodialysis. Biological denitrification has low treatment efficiency for nitrate, especially for low-concentration nit...

Examples

Embodiment 1

[0026] (1) Aggregation:

[0027] (1) Preparation of the water phase: 232.85ml of 2.5% polyvinyl alcohol (PVA) solution, 60.48ml of gelatin solution with a mass fraction of 2%, 9.07g of tricalcium phosphate, 3.02g of sodium chloride, and a mass fraction of 1‰ Mix 9.07ml of methylene blue solution and 0.15g of EDTA evenly and set aside.

[0028] (2) Preparation of the oil phase: Mix 80mL of styrene, 4mL of divinylbenzene, 0.8g of benzoyl peroxide and 67.2mL of liquid paraffin for later use.

[0029] (3) Operation process: Add the water phase to a 500ml three-neck flask with stirring, condenser, and thermometer, and stir at 200r / min. When the water bath is heated to 60°C, add the pre-prepared oil phase, increase the stirring speed to 400r / min, and stir After 15 minutes, raise the temperature to 75°C and keep it warm for 2 hours; then raise the temperature to 80°C and keep it warm for 1-2 hours; finally raise the temperature to 90°C-95°C and keep it warm for 4 hours.

[0030] Af...

Embodiment 2

[0039] (1) Aggregation:

[0040] (1) Preparation of the water phase: 243.94ml of 2.5% polyvinyl alcohol (PVA) solution, 63.36ml of gelatin solution with a mass fraction of 2%, 9.5g of tricalcium phosphate, 3.17g of sodium chloride, and a mass fraction of 1‰ Mix 9.5ml of methylene blue solution and 0.16g of EDTA evenly and set aside.

[0041] (2) Preparation of the oil phase: Mix 80mL of styrene, 8mL of divinylbenzene, 0.9g of benzoyl peroxide and 70.4mL of liquid paraffin for later use.

[0042] (3) Operation process: Add the water phase to a 500ml three-neck flask with stirring, condenser, and thermometer, and stir at 200r / min. When the water bath is heated to 60°C, add the pre-prepared oil phase, increase the stirring speed to 400r / min, and stir After 15 minutes, raise the temperature to 75°C and keep it warm for 2 hours; then raise the temperature to 80°C and keep it warm for 1-2 hours; finally raise the temperature to 90°C-95°C and keep it warm for 4 hours. After the rea...

technical field

[0001] The invention belongs to the preparation process of ion exchange resins, in particular to a preparation method of macroporous strongly basic styrene-based anion exchange resins for removing nitrate in water. Background technique

[0002] After nitrate enters the human body, it is easily reduced to nitrite and causes methemoglobinemia, and it also has the risk of causing cancer in the human body. In addition, nitrogen is one of the important nutrient sources that cause eutrophication of water bodies. Therefore, how to remove nitrogen in water cost-effectively has always been one of the current engineering problems in water quality security and water environment protection. At present, the main methods for treating wastewater polluted by nitrates are: ion exchange, biological denitrification, chemical reduction, reverse osmosis and electrodialysis. Biological denitrification has low treatment efficiency for nitrate, especially for low-concentration nit...

Examples

Embodiment 1

[0026] (1) Aggregation:

[0027] (1) Preparation of the water phase: 232.85ml of 2.5% polyvinyl alcohol (PVA) solution, 60.48ml of gelatin solution with a mass fraction of 2%, 9.07g of tricalcium phosphate, 3.02g of sodium chloride, and a mass fraction of 1‰ Mix 9.07ml of methylene blue solution and 0.15g of EDTA evenly and set aside.

[0028] (2) Preparation of the oil phase: Mix 80mL of styrene, 4mL of divinylbenzene, 0.8g of benzoyl peroxide and 67.2mL of liquid paraffin for later use.

[0029] (3) Operation process: Add the water phase to a 500ml three-neck flask with stirring, condenser, and thermometer, and stir at 200r / min. When the water bath is heated to 60°C, add the pre-prepared oil phase, increase the stirring speed to 400r / min, and stir After 15 minutes, raise the temperature to 75°C and keep it warm for 2 hours; then raise the temperature to 80°C and keep it warm for 1-2 hours; finally raise the temperature to 90°C-95°C and keep it warm for 4 hours.

[0030] Af...

Embodiment 2

[0039] (1) Aggregation:

[0040] (1) Preparation of the water phase: 243.94ml of 2.5% polyvinyl alcohol (PVA) solution, 63.36ml of gelatin solution with a mass fraction of 2%, 9.5g of tricalcium phosphate, 3.17g of sodium chloride, and a mass fraction of 1‰ Mix 9.5ml of methylene blue solution and 0.16g of EDTA evenly and set aside.

[0041] (2) Preparation of the oil phase: Mix 80mL of styrene, 8mL of divinylbenzene, 0.9g of benzoyl peroxide and 70.4mL of liquid paraffin for later use.

[0042] (3) Operation process: Add the water phase to a 500ml three-neck flask with stirring, condenser, and thermometer, and stir at 200r / min. When the water bath is heated to 60°C, add the pre-prepared oil phase, increase the stirring speed to 400r / min, and stir After 15 minutes, raise the temperature to 75°C and keep it warm for 2 hours; then raise the temperature to 80°C and keep it warm for 1-2 hours; finally raise the temperature to 90°C-95°C and keep it warm for 4 hours. After the rea...