Metallurgy ore pulp separation polyacrylamide preparation method
The separation of polyacrylamide by the synthesis of metallurgical slurry with introduced quaternary ammonium groups and sulfonic acid groups was solved, and the problems of poor flocculation effect and insufficient high-temperature resistance in the prior art were achieved, and excellent flocculation effect and rapid precipitation effect were achieved at high temperatures.
Patent Information
- Application Number
- CN202510452612.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-11
- Publication Date
- 2025-07-11
AI Technical Summary
The flocculation effect of existing polyacrylamides needs to be improved during the separation of metallurgical slurry, and its high-temperature resistance is insufficient, resulting in a significant decrease in the flocculation effect at high temperatures, affecting the separation efficiency.
Polyacrylamide is separated by a series of chemical reactions by synthesizing metallurgical slurry, introducing quaternary ammonium groups and sulfonic acid groups to enhance the flocculation effect, and introducing triazine ring structures and benzene rings on the molecular structure through hyperbranching modifiers to improve high temperature stability.
It achieves excellent flocculation effect under high temperature environments, can quickly remove rubber particles with different charges, and is suitable for treating metallurgical slurries of different temperatures.
Smart Images
Figure BDA0005354545080000141 
Figure BDA0005354545080000142
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of metallurgical pulp separation, and particularly relates to a preparation method of polyacrylamide for metallurgical pulp separation. Background Art
[0002] As an important polymer flocculant, polyacrylamide has wide applications in the fields of metallurgy, chemical engineering, water treatment, etc. Especially in the process of metallurgical pulp separation, polyacrylamide can effectively improve the sedimentation rate of solid particles in the pulp and achieve efficient separation. However, the existing polyacrylamide has room for improvement in flocculation effect and has deficiencies in high-temperature resistance. When the pulp temperature is relatively high, the flocculation effect of polyacrylamide will decrease significantly, and even lead to flocculation failure, affecting the separation efficiency and separation effect of metallurgical pulp. Therefore, it is of great significance to develop a preparation method of polyacrylamide for metallurgical pulp separation. Summary of the Invention
[0003] In order to overcome the above technical problems, the purpose of the present invention is to provide a preparation method of polyacrylamide for metallurgical pulp separation, which solves the problems that the existing polyacrylamide has room for improvement in flocculation effect and has deficiencies in high-temperature resistance.
[0004] The purpose of the present invention can be achieved by the following technical solutions:
[0005] A preparation method of polyacrylamide for metallurgical pulp separation includes the following steps:
[0006] Step 1: Add 4-bromo-1,8-naphthalic anhydride, tetrabutylammonium iodide, and anhydrous tetrahydrofuran into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 20 - 30 min under the conditions of a temperature of 0 - 5°C and a stirring rate of 300 - 400 r / min. Then, while stirring, gradually dropwise add 3-buten-1-ol, control the dropping rate at 1 - 2 drops / s. After the dropping is completed, continue to stir and react at a temperature of 25 - 30°C for 15 - 20 h. After the reaction ends, add the reaction product into ice water, then extract with anhydrous ether 2 - 3 times, combine the extraction liquid and wash it with saturated brine 2 - 3 times, then dry it with anhydrous sodium sulfate, then perform vacuum filtration, and rotate and evaporate the filtrate to remove the solvent to obtain the acid anhydride monomer;
[0007] Step 2: Add melamine, triethylamine, and anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 30 - 50 min under the conditions of a temperature of 25 - 30°C and a stirring rate of 300 - 400 r / min. Then, while stirring, gradually add a solution of phenyl dichlorophosphate dropwise, controlling the dropping rate at 1 - 2 drops / s. After the addition is complete, raise the temperature to 80 - 85°C and continue to stir and react for 10 - 12 h. After the reaction is completed, cool the reaction product to room temperature, then rotary evaporate to remove the solvent. Then add it to dimethyl sulfoxide, and then perform vacuum filtration. Rotary evaporate the filtrate to remove the solvent, then wash it 2 - 3 times with distilled water and anhydrous ethanol in sequence. Then place it in a vacuum drying oven and dry it for 2 - 3 h under the condition of a temperature of 70 - 75°C to obtain a hyperbranched modifier;
[0008] Step 3: Add 6-bromo-1-hexanol, aqueous dimethylamine solution, and anhydrous ethanol into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a reflux condenser. Introduce nitrogen for protection. Stir and react for 20 - 30 min under the conditions of a temperature of 25 - 30°C and a stirring rate of 300 - 400 r / min. Then raise the temperature to 80 - 85°C and continue to stir and react for 10 - 15 h. After the reaction is completed, cool the reaction product to room temperature, then rotary evaporate to remove the solvent. Then add it to a sodium bicarbonate solution, and then extract it 2 - 3 times with chloroform. Combine the extracts and dry them with anhydrous sodium sulfate. Then perform vacuum filtration. Rotary evaporate the filtrate to remove the solvent to obtain Intermediate 1;
[0009] Step 4: Add Intermediate 1, triethylamine, and anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 30 - 50 min under the conditions of a temperature of -5 - 0°C and a stirring rate of 300 - 400 r / min. Then, while stirring, gradually add methacryloyl chloride dropwise, controlling the dropping rate at 1 - 2 drops / s. After the addition is complete, raise the temperature to 25 - 30°C and continue to stir and react for 10 - 12 h. After the reaction is completed, add the reaction product to a sodium bicarbonate solution, and then extract it 2 - 3 times with dichloromethane. Combine the extracts and dry them with anhydrous sodium sulfate. Then perform vacuum filtration. Rotary evaporate the filtrate to remove the solvent to obtain Intermediate 2;
[0010] Step 5: Add Intermediate 2, 1,4-butanesultone, 4-methoxyphenol, and anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a reflux condenser. Introduce nitrogen for protection. Stir and react for 25 - 30 h under the conditions of a temperature of 35 - 40°C and a stirring rate of 300 - 400 r / min. After the reaction is completed, cool the reaction product to -20°C and maintain it for 10 - 12 h. Then perform vacuum filtration. Rotary evaporate the filtrate to remove the solvent, and then recrystallize it with anhydrous ether to obtain a dual-ion monomer;
[0011] Step 6: Add acrylamide, diionic monomer, anhydride monomer, sodium dodecylbenzenesulfonate, and deionized water into a three-necked flask equipped with a stirrer, thermometer, gas pipe, and constant pressure dropping funnel. Introduce nitrogen for protection. Stir and react for 20 - 30 min under the conditions of a temperature of 25 - 30 °C and a stirring rate of 300 - 400 r / min. Then add azobisisobutyronitrile and continue to stir and react for 8 - 10 h under the condition of heating to 70 - 75 °C. Then add the hyperbranched modifier and continue to stir and react for 4 - 5 h under the condition of heating to 85 - 90 °C. After the reaction is completed, cool the reaction product to room temperature, then perform vacuum filtration. Wash the filter cake with absolute ethanol 2 - 3 times, and then place it in a vacuum drying oven and dry it for 3 - 4 h under the condition of a temperature of 70 - 75 °C to obtain the metallurgical pulp separation polyacrylamide.
[0012] As a further scheme of the present invention: The dosage ratio of the 4-bromo-1,8-naphthalic anhydride, tetrabutylammonium iodide, anhydrous tetrahydrofuran, and 3-buten-1-ol in Step 1 is 11 - 13 mmol: 0.01 - 0.03 g: 50 - 55 mL: 10 mmol.
[0013] As a further scheme of the present invention: The dosage ratio of the melamine, triethylamine, anhydrous acetonitrile, and phenyl dichlorophosphate solution in Step 2 is 10 mmol: 35 - 40 mmol: 50 - 60 mL: 30 - 35 mL.
[0014] As a further scheme of the present invention: The phenyl dichlorophosphate solution in Step 2 is a solution formed by dissolving phenyl dichlorophosphate in an amount of 10 - 12 mmol: 8 mL in anhydrous acetonitrile.
[0015] As a further scheme of the present invention: The dosage ratio of the 6-bromohexanol, aqueous dimethylamine solution, and absolute ethanol in Step 3 is 2 g: 30 - 35 mL: 40 - 50 mL.
[0016] As a further scheme of the present invention: The mass fraction of the aqueous dimethylamine solution in Step 3 is 40%; the mass fraction of the sodium bicarbonate solution is 5 - 6%.
[0017] As a further scheme of the present invention: The dosage ratio of the intermediate 1, triethylamine, anhydrous acetonitrile, and methacryloyl chloride in Step 4 is 10 mmol: 11 - 13 mmol: 70 - 80 mL: 11 - 13 mmol.
[0018] As a further scheme of the present invention: The mass fraction of the sodium bicarbonate solution in Step 4 is 5 - 6%.
[0019] As a further solution of the present invention: the dosage ratio of the intermediate 2, 1,4-butanesultone, 4-methoxyphenol and anhydrous acetonitrile in step five is 10 mmol: 15-19 mmol: 0.1-0.2 g: 80-100 mL.
[0020] As a further solution of the present invention: the dosage ratio of acrylamide, double ion monomer, acid anhydride monomer, sodium dodecylbenzenesulfonate, deionized water, azobisisobutyronitrile and hyperbranched modifier in step six is 12-16 g: 2-2.5 g: 1.2-1.8 g: 0.01-0.02 g: 50-55 mL: 0.15-0.25 g: 0.5-0.9 g.
[0021] Beneficial effects of the present invention:
[0022] A preparation method of polyacrylamide for metallurgical pulp separation according to the present invention, firstly, 4-bromo-1,8-naphthalic anhydride reacts with 3-buten-1-ol, and the bromine atom on 4-bromo-1,8-naphthalic anhydride reacts with the hydroxyl group on 3-buten-1-ol, and at the same time, an alkenyl group is introduced to obtain an acid anhydride monomer. Then, melamine reacts with phenyl dichlorophosphate, and the amino group on melamine reacts with the chlorine atom on phenyl dichlorophosphate, and crosslinking occurs step by step to obtain a hyperbranched modifier. Then, 6-bromohexanol reacts with dimethylamine, and the bromine atom on 6-bromohexanol reacts with N-H on dimethylamine to form a tertiary amine group to obtain intermediate 1. Then, intermediate 1 reacts with methacryloyl chloride, and the hydroxyl group on intermediate 1 reacts with the acyl chloride group on methacryloyl chloride to introduce an alkenyl group to obtain intermediate 2. Then, intermediate 2 reacts with 1,4-butanesultone, and the tertiary amine group on intermediate 2 undergoes a ring-opening reaction with 1,4-butanesultone to form a quaternary ammonium group, and at the same time, a sulfonic acid group is introduced to obtain a double ion monomer. Finally, acrylamide, double ion monomer, and acid anhydride monomer are used as polymerization monomers for polymerization, and the amino group on the hyperbranched modifier reacts with the acid anhydride group on the polymer molecular chain to introduce a branched chain to obtain polyacrylamide for metallurgical pulp separation. The polyacrylamide for metallurgical pulp separation introduces a quaternary ammonium group and a sulfonic acid group in its molecular structure through the double ion monomer. The quaternary ammonium group is positively charged and can combine with negatively charged colloids in water through charge neutralization, making the colloids destabilize and precipitate. The sulfonic acid group is negatively charged and can combine with positively charged colloids in water through charge neutralization, making the colloids destabilize and precipitate. It can simultaneously remove positively charged and negatively charged colloids in water, with a fast colloid removal rate and good flocculation effect, and is suitable for treating metallurgical pulp with different charges. Through the hyperbranched modifier, a large number of triazine ring structures, benzene rings, and P elements can be introduced into its molecular structure, endowing it with excellent high-temperature stability, so that it can still maintain excellent flocculation effect under high-temperature environment and is suitable for treating metallurgical pulp at different temperatures. Specific embodiments
[0023] The following will describe the technical solutions in the embodiments of the present invention clearly and completely in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts belong to the scope of protection of the present invention.
[0024] Embodiment 1:
[0025] This embodiment is a method for preparing polyacrylamide for metallurgical pulp separation, including the following steps:
[0026] Step 1: Add 11 mmol of 4-bromo-1,8-naphthalic anhydride, 0.01 g of tetrabutylammonium iodide, and 50 mL of anhydrous tetrahydrofuran into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react at a temperature of 0 °C and a stirring rate of 300 r / min for 20 min. Then, while stirring, gradually dropwise add 10 mmol of 3-buten-1-ol, controlling the dropping rate at 1 drop / s. After the addition is complete, continue to stir and react at a temperature of 25 °C for 15 h. After the reaction is completed, add the reaction product into ice water, then extract it twice with anhydrous ether, combine the extraction solutions, wash them twice with saturated brine, then dry them with anhydrous sodium sulfate, and then perform vacuum filtration. Rotate-evaporate the filtrate to remove the solvent to obtain the acid anhydride monomer;
[0027] Step 2: Add 10 mmol of melamine, 35 mmol of triethylamine, and 50 mL of anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react at a temperature of 25 °C and a stirring rate of 300 r / min for 30 min. Then, while stirring, gradually dropwise add a solution of 30 mL of phenyl dichlorophosphate dissolved in anhydrous acetonitrile according to 10 mmol:8 mL, controlling the dropping rate at 1 drop / s. After the addition is complete, continue to stir and react at a temperature of 80 °C for 10 h. After the reaction is completed, cool the reaction product to room temperature, then rotate-evaporate to remove the solvent, then add it into dimethyl sulfoxide, then perform vacuum filtration, rotate-evaporate the filtrate to remove the solvent, then wash it twice with distilled water and anhydrous ethanol in sequence, and then place it in a vacuum drying oven and dry it at a temperature of 70 °C for 2 h to obtain the hyperbranched modifier;
[0028] Step 3: Add 2 g of 6-bromohexanol, 30 mL of 40% (by mass) aqueous dimethylamine solution, and 40 mL of absolute ethanol into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a reflux condenser. Protect with nitrogen. Stir and react for 20 min at a temperature of 25 °C and a stirring rate of 300 r / min. Then, continue to stir and react for 10 h at a temperature of 80 °C. After the reaction is completed, cool the reaction product to room temperature. Then, remove the solvent by rotary evaporation. Then, add it into a 5% (by mass) sodium bicarbonate solution. Then, extract twice with chloroform. Combine the extracts and dry with anhydrous sodium sulfate. Then, perform vacuum filtration. Rotate and evaporate the filtrate to remove the solvent to obtain Intermediate 1;
[0029] Step 4: Add 10 mmol of Intermediate 1, 11 mmol of triethylamine, and 70 mL of absolute acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 30 min at a temperature of -5 °C and a stirring rate of 300 r / min. Then, gradually add 11 mmol of methacryloyl chloride dropwise with stirring, controlling the dropping rate at 1 drop / s. After the addition is complete, continue to stir and react for 10 h at a temperature of 25 °C. After the reaction is completed, add the reaction product into a 5% (by mass) sodium bicarbonate solution. Then, extract twice with dichloromethane. Combine the extracts and dry with anhydrous sodium sulfate. Then, perform vacuum filtration. Rotate and evaporate the filtrate to remove the solvent to obtain Intermediate 2;
[0030] Step 5: Add 10 mmol of Intermediate 2, 15 mmol of 1,4-butanesultone, 0.1 g of 4-methoxyphenol, and 80 mL of absolute acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a reflux condenser. Protect with nitrogen. Stir and react for 25 h at a temperature of 35 °C and a stirring rate of 300 r / min. After the reaction is completed, cool the reaction product to -20 °C and maintain for 10 h. Then, perform vacuum filtration. Rotate and evaporate the filtrate to remove the solvent. Then, recrystallize with anhydrous ether to obtain the double-ion monomer;
[0031] Step 6: Add 12 g of acrylamide, 2 g of double ionic monomer, 1.2 g of acid anhydride monomer, 0.01 g of sodium dodecylbenzenesulfonate, and 50 mL of deionized water into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a constant pressure dropping funnel. Introduce nitrogen for protection. Stir and react for 20 min under the conditions of a temperature of 25°C and a stirring rate of 300 r / min. Then add 0.15 g of azobisisobutyronitrile and continue to stir and react for 8 h under the condition of heating to 70°C. Then add 0.5 g of hyperbranched modifier and continue to stir and react for 4 h under the condition of heating to 85°C. After the reaction is completed, cool the reaction product to room temperature, then perform vacuum filtration. Wash the filter cake twice with absolute ethanol, and then place it in a vacuum drying oven and dry it for 3 h under the condition of a temperature of 70°C to obtain metallurgical pulp separation polyacrylamide.
[0032] Example 2:
[0033] This example is a method for preparing metallurgical pulp separation polyacrylamide, including the following steps:
[0034] Step 1: Add 12 mmol of 4-bromo-1,8-naphthalic anhydride, 0.02 g of tetrabutylammonium iodide, and 52 mL of anhydrous tetrahydrofuran into a three-necked flask equipped with a stirrer, a thermometer, and a constant pressure dropping funnel. Stir and react for 25 min under the conditions of a temperature of 2°C and a stirring rate of 350 r / min. Then, while stirring, gradually add dropwise 10 mmol of 3-buten-1-ol, controlling the dropping rate at 1 drop / s. After the dropping is completed, continue to stir and react for 18 h under the condition of heating to 28°C. After the reaction is completed, add the reaction product into ice water, then extract it twice with anhydrous ether, combine the extraction liquids and wash them twice with saturated brine, then dry them with anhydrous sodium sulfate, then perform vacuum filtration, and rotate and evaporate the filtrate to remove the solvent to obtain the acid anhydride monomer;
[0035] Step 2: Add 10 mmol of melamine, 38 mmol of triethylamine, and 55 mL of anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant pressure dropping funnel. Stir and react for 40 min under the conditions of a temperature of 28°C and a stirring rate of 350 r / min. Then, while stirring, gradually add dropwise a solution of 32 mL of phenyl dichlorophosphate dissolved in anhydrous acetonitrile according to 11 mmol:8 mL, controlling the dropping rate at 1 drop / s. After the dropping is completed, continue to stir and react for 11 h under the condition of heating to 82°C. After the reaction is completed, cool the reaction product to room temperature, then rotate and evaporate to remove the solvent, then add it into dimethyl sulfoxide, then perform vacuum filtration, rotate and evaporate the filtrate to remove the solvent, then wash it twice with distilled water and twice with absolute ethanol, and then place it in a vacuum drying oven and dry it for 2.5 h under the condition of a temperature of 72°C to obtain the hyperbranched modifier;
[0036] Step 3: Add 2 g of 6-bromohexanol, 32 mL of 40% (by mass) aqueous dimethylamine solution, and 45 mL of absolute ethanol into a three-necked flask equipped with a stirrer, a thermometer, a gas inlet tube, and a reflux condenser. Protect with nitrogen. Stir and react at a temperature of 28 °C and a stirring rate of 350 r / min for 25 min. Then, continue to stir and react at a temperature of 82 °C for 12 h. After the reaction is completed, cool the reaction product to room temperature, then rotary evaporate to remove the solvent. Then, add it to a 5.5% (by mass) sodium bicarbonate solution, extract twice with chloroform, combine the extracts and dry with anhydrous sodium sulfate. Then, perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent to obtain Intermediate 1;
[0037] Step 4: Add 10 mmol of Intermediate 1, 12 mmol of triethylamine, and 75 mL of absolute acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react at a temperature of -3 °C and a stirring rate of 350 r / min for 40 min. Then, gradually add 12 mmol of methacryloyl chloride dropwise with stirring, control the dropping rate at 1 drop / s. After the addition is completed, continue to stir and react at a temperature of 28 °C for 11 h. After the reaction is completed, add the reaction product to a 5.5% (by mass) sodium bicarbonate solution, extract twice with dichloromethane, combine the extracts and dry with anhydrous sodium sulfate. Then, perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent to obtain Intermediate 2;
[0038] Step 5: Add 10 mmol of Intermediate 2, 17 mmol of 1,4-butanesultone, 0.15 g of 4-methoxyphenol, and 90 mL of absolute acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, a gas inlet tube, and a reflux condenser. Protect with nitrogen. Stir and react at a temperature of 38 °C and a stirring rate of 350 r / min for 28 h. After the reaction is completed, cool the reaction product to -20 °C and maintain for 11 h. Then, perform vacuum filtration, rotary evaporate the filtrate to remove the solvent, and then recrystallize with anhydrous ether to obtain the double-ion monomer;
[0039] Step 6: Add 14 g of acrylamide, 2.2 g of double ionic monomer, 1.5 g of acid anhydride monomer, 0.015 g of sodium dodecylbenzenesulfonate, and 52 mL of deionized water into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a constant-pressure dropping funnel. Introduce nitrogen for protection. Stir and react for 25 min at a temperature of 28 °C and a stirring rate of 350 r / min. Then add 0.20 g of azobisisobutyronitrile and continue to stir and react for 9 h under the condition of raising the temperature to 72 °C. Then add 0.7 g of hyperbranched modifier and continue to stir and react for 4.5 h under the condition of raising the temperature to 88 °C. After the reaction is completed, cool the reaction product to room temperature, then perform vacuum filtration. Wash the filter cake twice with absolute ethanol, and then place it in a vacuum drying oven and dry it for 3.5 h at a temperature of 72 °C to obtain metallurgical pulp separation polyacrylamide.
[0040] Example 3:
[0041] This example is a preparation method of metallurgical pulp separation polyacrylamide, which includes the following steps:
[0042] Step 1: Add 13 mmol of 4-bromo-1,8-naphthalic anhydride, 0.03 g of tetrabutylammonium iodide, and 55 mL of anhydrous tetrahydrofuran into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 30 min at a temperature of 5 °C and a stirring rate of 400 r / min. Then, while stirring, gradually dropwise add 10 mmol of 3-buten-1-ol, controlling the dropping rate at 2 drops / s. After the dropping is completed, continue to stir and react for 20 h under the condition of raising the temperature to 30 °C. After the reaction is completed, add the reaction product into ice water, then extract it 3 times with anhydrous ether, combine the extraction liquid and wash it 3 times with saturated brine, then dry it with anhydrous sodium sulfate, then perform vacuum filtration, and rotate and evaporate the filtrate to remove the solvent to obtain the acid anhydride monomer;
[0043] Step 2: Add 10 mmol of melamine, 40 mmol of triethylamine, and 60 mL of anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 50 min at a temperature of 30 °C and a stirring rate of 400 r / min. Then, while stirring, gradually dropwise add a dichlorophenyl phosphate solution formed by dissolving 35 mL of dichlorophenyl phosphate in anhydrous acetonitrile according to 12 mmol:8 mL, controlling the dropping rate at 2 drops / s. After the dropping is completed, continue to stir and react for 12 h under the condition of raising the temperature to 85 °C. After the reaction is completed, cool the reaction product to room temperature, then rotate and evaporate to remove the solvent, then add it into dimethyl sulfoxide, then perform vacuum filtration, rotate and evaporate the filtrate to remove the solvent, then wash it 3 times with distilled water and absolute ethanol in sequence, and then place it in a vacuum drying oven and dry it for 3 h at a temperature of 75 °C to obtain the hyperbranched modifier;
[0044] Step 3: Add 2 g of 6-bromohexanol, 35 mL of 40% (mass fraction) aqueous dimethylamine solution, and 50 mL of absolute ethanol into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a reflux condenser. Introduce nitrogen for protection. Stir and react for 30 min under the conditions of a temperature of 30°C and a stirring rate of 400 r / min. Then, raise the temperature to 85°C and continue stirring and reacting for 15 h. After the reaction is completed, cool the reaction product to room temperature, then remove the solvent by rotary evaporation. Then, add it into a 6% (mass fraction) sodium bicarbonate solution, and extract it 3 times with chloroform. Combine the extraction liquids and dry them with anhydrous sodium sulfate. Then, perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent to obtain Intermediate 1;
[0045] Step 4: Add 10 mmol of Intermediate 1, 13 mmol of triethylamine, and 80 mL of absolute acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 50 min under the conditions of a temperature of 0°C and a stirring rate of 400 r / min. Then, gradually add 13 mmol of methacryloyl chloride dropwise while stirring, controlling the dropping rate at 2 drops / s. After the addition is completed, raise the temperature to 30°C and continue stirring and reacting for 12 h. After the reaction is completed, add the reaction product into a 6% (mass fraction) sodium bicarbonate solution, and extract it 3 times with dichloromethane. Combine the extraction liquids and dry them with anhydrous sodium sulfate. Then, perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent to obtain Intermediate 2;
[0046] Step 5: Add 10 mmol of Intermediate 2, 19 mmol of 1,4-butanesultone, 0.2 g of 4-methoxyphenol, and 100 mL of absolute acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a reflux condenser. Introduce nitrogen for protection. Stir and react for 30 h under the conditions of a temperature of 40°C and a stirring rate of 400 r / min. After the reaction is completed, cool the reaction product to -20°C and maintain it for 12 h. Then, perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent. Then, recrystallize it with anhydrous ether to obtain the double-ion monomer;
[0047] Step 6: Add 16 g of acrylamide, 2.5 g of double-ion monomer, 1.8 g of acid anhydride monomer, 0.02 g of sodium dodecylbenzenesulfonate, and 55 mL of deionized water into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a constant-pressure dropping funnel. Introduce nitrogen for protection. Stir and react for 30 min at a temperature of 30 °C and a stirring rate of 400 r / min. Then add 0.25 g of azobisisobutyronitrile and continue to stir and react for 10 h under the condition of heating to 75 °C. Then add 0.9 g of hyperbranched modifier and continue to stir and react for 5 h under the condition of heating to 90 °C. After the reaction is completed, cool the reaction product to room temperature, then carry out vacuum filtration. Wash the filter cake with absolute ethanol three times, and then place it in a vacuum drying oven and dry it for 4 h at a temperature of 75 °C to obtain metallurgical pulp separation polyacrylamide.
[0048] Comparative Example 1:
[0049] This comparative example is a method for preparing metallurgical pulp separation polyacrylamide, which includes the following steps:
[0050] Add 16 g of acrylamide, 0.02 g of sodium dodecylbenzenesulfonate, and 55 mL of deionized water into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a constant-pressure dropping funnel. Introduce nitrogen for protection. Stir and react for 30 min at a temperature of 30 °C and a stirring rate of 400 r / min. Then add 0.25 g of azobisisobutyronitrile and continue to stir and react for 10 h under the condition of heating to 75 °C. Then continue to stir and react for 5 h under the condition of heating to 90 °C. After the reaction is completed, cool the reaction product to room temperature, then carry out vacuum filtration. Wash the filter cake with absolute ethanol three times, and then place it in a vacuum drying oven and dry it for 4 h at a temperature of 75 °C to obtain metallurgical pulp separation polyacrylamide.
[0051] Comparative Example 2:
[0052] This comparative example is a method for preparing metallurgical pulp separation polyacrylamide, which includes the following steps:
[0053] Step 1: Add 13 mmol of 4-bromo-1,8-naphthalic anhydride, 0.03 g of tetrabutylammonium iodide, and 55 mL of anhydrous tetrahydrofuran into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 30 min at a temperature of 5 °C and a stirring rate of 400 r / min. Then, while stirring, gradually add dropwise 10 mmol of 3-buten-1-ol, controlling the dropping rate at 2 drops / s. After the addition is complete, continue to stir and react at 30 °C for 20 h. After the reaction is completed, add the reaction product into ice water, then extract it 3 times with anhydrous ether. Combine the extraction solutions and wash them 3 times with saturated brine, then dry with anhydrous sodium sulfate, and then perform vacuum filtration. Rotate and evaporate the filtrate to remove the solvent to obtain the acid anhydride monomer;
[0054] Step 2: Add 10 mmol of melamine, 40 mmol of triethylamine, and 60 mL of anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 50 min at a temperature of 30 °C and a stirring rate of 400 r / min. Then, while stirring, gradually add dropwise a solution of 35 mL of phenyl dichlorophosphate dissolved in anhydrous acetonitrile according to 12 mmol:8 mL, controlling the dropping rate at 2 drops / s. After the addition is complete, continue to stir and react at 85 °C for 12 h. After the reaction is completed, cool the reaction product to room temperature, then rotate and evaporate to remove the solvent, then add it into dimethyl sulfoxide, and then perform vacuum filtration. Rotate and evaporate the filtrate to remove the solvent, then wash it 3 times with distilled water and anhydrous ethanol in sequence, and then place it in a vacuum drying oven and dry it at 75 °C for 3 h to obtain the hyperbranched modifier;
[0055] Step 3: Add 16 g of acrylamide, 1.8 g of the acid anhydride monomer, 0.02 g of sodium dodecylbenzenesulfonate, and 55 mL of deionized water into a three-necked flask equipped with a stirrer, a thermometer, a gas guide tube, and a constant-pressure dropping funnel. Pass nitrogen for protection. Stir and react for 30 min at a temperature of 30 °C and a stirring rate of 400 r / min. Then, add 0.25 g of azobisisobutyronitrile and continue to stir and react at 75 °C for 10 h. Then, add 0.9 g of the hyperbranched modifier and continue to stir and react at 90 °C for 5 h. After the reaction is completed, cool the reaction product to room temperature, then perform vacuum filtration. Wash the filter cake 3 times with anhydrous ethanol, and then place it in a vacuum drying oven and dry it at 75 °C for 4 h to obtain the metallurgical pulp separation polyacrylamide.
[0056] Comparative Example 3:
[0057] This comparative example is a preparation method of metallurgical pulp separation polyacrylamide, including the following steps:
[0058] Step 1: Add 2 g of 6-bromohexanol, 35 mL of 40% (by mass) aqueous dimethylamine solution, and 50 mL of absolute ethanol into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a reflux condenser. Protect with nitrogen. Stir and react for 30 min at a temperature of 30 °C and a stirring rate of 400 r / min. Then, continue to stir and react for 15 h under the condition of heating to 85 °C. After the reaction is completed, cool the reaction product to room temperature, then rotary evaporate to remove the solvent. Then, add it into a 6% (by mass) sodium bicarbonate solution, and then extract with chloroform three times. Combine the extracts and dry with anhydrous sodium sulfate. Then, perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent to obtain Intermediate 1;
[0059] Step 2: Add 10 mmol of Intermediate 1, 13 mmol of triethylamine, and 80 mL of absolute acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 50 min at a temperature of 0 °C and a stirring rate of 400 r / min. Then, gradually add 13 mmol of methacryloyl chloride dropwise while stirring, controlling the dropping rate at 2 drops / s. After the dropping is completed, continue to stir and react for 12 h under the condition of heating to 30 °C. After the reaction is completed, add the reaction product into a 6% (by mass) sodium bicarbonate solution, and then extract with dichloromethane three times. Combine the extracts and dry with anhydrous sodium sulfate. Then, perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent to obtain Intermediate 2;
[0060] Step 3: Add 10 mmol of Intermediate 2, 19 mmol of 1,4-butanesultone, 0.2 g of 4-methoxyphenol, and 100 mL of absolute acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a reflux condenser. Protect with nitrogen. Stir and react for 30 h at a temperature of 40 °C and a stirring rate of 400 r / min. After the reaction is completed, cool the reaction product to -20 °C and maintain for 12 h. Then, perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent. Then, recrystallize with anhydrous ether to obtain the double-ion monomer;
[0061] Step 4: Add 16 g of acrylamide, 2.5 g of the double-ion monomer, 0.02 g of sodium dodecylbenzenesulfonate, and 55 mL of deionized water into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a constant-pressure dropping funnel. Protect with nitrogen. Stir and react for 30 min at a temperature of 30 °C and a stirring rate of 400 r / min. Then, add 0.25 g of azobisisobutyronitrile and continue to stir and react for 10 h under the condition of heating to 75 °C. Then, continue to stir and react for 5 h under the condition of heating to 90 °C. After the reaction is completed, cool the reaction product to room temperature. Then, perform vacuum filtration, wash the filter cake three times with absolute ethanol, and then place it in a vacuum drying oven and dry at 75 °C for 4 h to obtain the polyacrylamide for metallurgical pulp separation.
[0062] The metallurgical pulp separation polyacrylamide of Examples 1-3 and Comparative Examples 1-3 was subjected to performance tests. 50 g of selenium-removed slag flotation tailings, 0.1 g of metallurgical pulp separation polyacrylamide, and 500 mL of distilled water at different temperatures were added to a beaker and stirred for 10 min to make the pulp concentration uniform. Then, the pulp was poured into a 1000 mL graduated cylinder and timing started. The sedimentation height at 5 min was recorded, and the supernatant state was observed. The test results are shown in the following table:
[0063]
[0064] Among them, the test pulp in the above results was prepared with distilled water at 25 °C;
[0065]
[0066] Among them, the test pulp in the above results was prepared with distilled water at 100 °C;
[0067] Among them, the chemical composition of the selenium-removed slag flotation tailings is as follows:
[0068] Element Pb Ba Sb S Te Bi As Fe Si Content, % 21.93 15.67 14.38 6.85 3.31 2.25 1.84 1.02 0.55
[0069] Referring to the data in the above table, from the comparison between Examples 1-3 and Comparative Examples 1-3, it can be seen that the metallurgical pulp separation polyacrylamide of the present application has excellent flocculation effect and good high-temperature stability.
[0070] In the description of this specification, the descriptions referring to terms such as "one embodiment", "example", "specific example", etc. mean that the specific features, structures, materials or characteristics described in connection with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.
[0071] The above content is only an example and explanation of the present invention. Those skilled in the art of this technology can make various modifications or supplements to the specific embodiments described or use similar methods to replace them. As long as they do not deviate from the invention or exceed the scope defined by this claim book, they should all belong to the protection scope of the present invention.
Claims
1. A preparation method of polyacrylamide for metallurgical pulp separation, characterized in that, It includes the following steps: Step 1: Add 4-bromo-1,8-naphthalic anhydride, tetrabutylammonium iodide, and anhydrous tetrahydrofuran into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 20 - 30 min under the conditions of a temperature of 0 - 5°C and a stirring rate of 300 - 400 r / min. Then, while stirring, gradually add 3-buten-1-ol dropwise, controlling the dropping rate at 1 - 2 drops / s. After the addition is complete, raise the temperature to 25 - 30°C and continue to stir and react for 15 - 20 h. After the reaction is completed, add the reaction product to ice water, then extract with anhydrous ether 2 - 3 times, combine the extraction solutions, wash with saturated brine 2 - 3 times, then dry with anhydrous sodium sulfate, then perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent to obtain the acid anhydride monomer; Step 2: Add melamine, triethylamine, and anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 30 - 50 min under the conditions of a temperature of 25 - 30°C and a stirring rate of 300 - 400 r / min. Then, while stirring, gradually add phenyl dichlorophosphate solution dropwise, controlling the dropping rate at 1 - 2 drops / s. After the addition is complete, raise the temperature to 80 - 85°C and continue to stir and react for 10 - 12 h. After the reaction is completed, cool the reaction product to room temperature, then rotary evaporate to remove the solvent, then add it to dimethyl sulfoxide, then perform vacuum filtration, rotary evaporate the filtrate to remove the solvent, then wash with distilled water and anhydrous ethanol 2 - 3 times in sequence, and then place it in a vacuum drying oven and dry at a temperature of 70 - 75°C for 2 - 3 h to obtain the hyperbranched modifier; Step 3: Add 6-bromohexanol, aqueous dimethylamine solution, and anhydrous ethanol into a three-necked flask equipped with a stirrer, a thermometer, a gas guide tube, and a reflux condenser. Protect with nitrogen. Stir and react for 20 - 30 min under the conditions of a temperature of 25 - 30°C and a stirring rate of 300 - 400 r / min. Then, raise the temperature to 80 - 85°C and continue to stir and react for 10 - 15 h. After the reaction is completed, cool the reaction product to room temperature, then rotary evaporate to remove the solvent, then add it to sodium bicarbonate solution, then extract with chloroform 2 - 3 times, combine the extraction solutions, dry with anhydrous sodium sulfate, then perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent to obtain Intermediate 1; Step 4: Add Intermediate 1, triethylamine, and anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, and a constant-pressure dropping funnel. Stir and react for 30 - 50 min under the conditions of a temperature of -5 - 0°C and a stirring rate of 300 - 400 r / min. Then, while stirring, gradually add methacryloyl chloride dropwise, controlling the dropping rate at 1 - 2 drops / s. After the addition is complete, raise the temperature to 25 - 30°C and continue to stir and react for 10 - 12 h. After the reaction is completed, add the reaction product to sodium bicarbonate solution, then extract with dichloromethane 2 - 3 times, combine the extraction solutions, dry with anhydrous sodium sulfate, then perform vacuum filtration, and rotary evaporate the filtrate to remove the solvent to obtain Intermediate 2; Step 5: Add intermediate 2, 1,4-butanesultone, 4-methoxyphenol, and anhydrous acetonitrile into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a reflux condenser. Protect with nitrogen. Stir and react at a temperature of 35 - 40 °C and a stirring rate of 300 - 400 r / min for 25 - 30 h. After the reaction is completed, cool the reaction product to -20 °C and maintain for 10 - 12 h. Then perform vacuum filtration. Rotate evaporate the filtrate to remove the solvent. Then recrystallize with anhydrous ether to obtain the double ion monomer; Step 6: Add acrylamide, the double ion monomer, the acid anhydride monomer, sodium dodecylbenzenesulfonate, and deionized water into a three-necked flask equipped with a stirrer, a thermometer, a gas pipe, and a constant pressure dropping funnel. Protect with nitrogen. Stir and react at a temperature of 25 - 30 °C and a stirring rate of 300 - 400 r / min for 20 - 30 min. Then add azobisisobutyronitrile and continue to stir and react at a temperature of 70 - 75 °C for 8 - 10 h. Then add the hyperbranched modifier and continue to stir and react at a temperature of 85 - 90 °C for 4 - 5 h. After the reaction is completed, cool the reaction product to room temperature. Then perform vacuum filtration. Wash the filter cake with anhydrous ethanol 2 - 3 times. Then place it in a vacuum drying oven and dry at a temperature of 70 - 75 °C for 3 - 4 h to obtain the metallurgical pulp separation polyacrylamide.
2. The preparation method of polyacrylamide for metallurgical pulp separation according to claim 1, characterized in that, The dosage ratio of the 4-bromo-1,8-naphthalic anhydride, tetrabutylammonium iodide, anhydrous tetrahydrofuran, and 3-buten-1-ol in Step 1 is 11 - 13 mmol: 0.01 - 0.03 g: 50 - 55 mL: 10 mmol.
3. A preparation method of polyacrylamide for metallurgical pulp separation according to claim 1, characterized in that The dosage ratio of the melamine, triethylamine, anhydrous acetonitrile, and phenyl dichlorophosphate solution in Step 2 is 10 mmol: 35 - 40 mmol: 50 - 60 mL: 30 - 35 mL.
4. A method for preparing polyacrylamide for metallurgical pulp separation according to claim 1, characterized in that, The phenyl dichlorophosphate solution in Step 2 is a solution formed by dissolving phenyl dichlorophosphate in anhydrous acetonitrile at a ratio of 10 - 12 mmol: 8 mL.
5. A method for preparing polyacrylamide for metallurgical pulp separation according to claim 1, characterized in that, The dosage ratio of the 6-bromohexanol, aqueous dimethylamine solution, and anhydrous ethanol in Step 3 is 2 g: 30 - 35 mL: 40 - 50 mL.
6. A method for preparing polyacrylamide for metallurgical pulp separation according to claim 1, characterized in that, The mass fraction of the aqueous dimethylamine solution in Step 3 is 40%; the mass fraction of the sodium bicarbonate solution is 5 - 6%.
7. A method for preparing polyacrylamide for metallurgical pulp separation according to claim 1, characterized in that, The dosage ratio of the intermediate 1, triethylamine, anhydrous acetonitrile, and methacryloyl chloride in Step 4 is 10 mmol: 11 - 13 mmol: 70 - 80 mL: 11 - 13 mmol.
8. A method for preparing polyacrylamide for metallurgical pulp separation according to claim 1, characterized in that, The mass fraction of the sodium bicarbonate solution in Step 4 is 5 - 6%.
9. A method for preparing polyacrylamide for metallurgical pulp separation according to claim 1, characterized in that, The dosage ratio of the intermediate 2, 1,4-butanesultone, 4-methoxyphenol, and anhydrous acetonitrile in Step 5 is 10 mmol: 15 - 19 mmol: 0.1 - 0.2 g: 80 - 100 mL.
10. A method for preparing polyacrylamide for metallurgical pulp separation according to claim 1, characterized in that, The dosage ratio of acrylamide, double ionic monomer, anhydride monomer, sodium dodecylbenzenesulfonate, deionized water, azodiisobutyronitrile and hyperbranched modifier in step six is 12-16 g: 2-2.5 g: 1.2-1.8 g: 0.01-0.02 g: 50-55 mL: 0.15-0.25 g: 0.5-0.9 g.