Desulfurization wastewater adsorption material and preparation method thereof

Abstract

The invention provides a desulfurization wastewater adsorption material and a preparation method thereof, and belongs to the technical field of composite materials. The desulfurization wastewater adsorption material provided by the invention is a non-woven fabric formed by modified fibers, adopts cheap and easily available polypropylene resin as a main raw material, is grafted with methacrylic acid, has a relatively high grafting rate, can be applied to purification of organic pollutants in desulfurization wastewater during pretreatment, has a good adsorption treatment effect, is not influenced by temperature, and is suitable for industrial production. The adsorption fibers are excellent in regeneration performance, and efficient operation of a membrane system is guaranteed. Results of the embodiment show that the removal rate of commercially available polypropylene fibers on the organic matters in the desulfurization wastewater is 56.42%, while the removal rate of the desulfurization wastewater adsorption material provided by the invention on the organic matters in the desulfurization wastewater reaches 93% or above, and the organic matters in the desulfurization wastewater can be efficiently removed.

Description

Technical Field

[0001] The present invention relates to the technical field of composite materials, and particularly to an adsorption material for desulfurized wastewater and a preparation method thereof. Background Art

[0002] During the flue gas desulfurization process in coal-fired power plants, a large amount of desulfurized wastewater is generated. The desulfurized wastewater contains a large amount of suspended solids, supersaturated sulfites, sulfates, heavy metal ions, organic pollutants, etc. Direct discharge will cause serious environmental problems. Therefore, the zero discharge of desulfurized wastewater is an important direction for thermal power plants to save water, reduce emissions, and promote sustainable development.

[0003] At present, the zero-discharge treatment process of desulfurized wastewater mainly includes three processes: pretreatment, salt concentration, and evaporation crystallization. Among them, pretreatment removes calcium and magnesium ions and particulate matter in the desulfurized wastewater through neutralization, sedimentation, flocculation, and clarification; then, through the concentration membrane technology, the low-concentration wastewater is further concentrated, which can effectively reduce the treatment water volume of the subsequent evaporation crystallization unit, thereby reducing the operating cost of the desulfurized wastewater zero-discharge process. However, although the current conventional pretreatment process of desulfurized wastewater has a good removal effect on calcium and magnesium ions and particulate matter in the wastewater, the removal effect on organic matter is limited. Due to different coal qualities and operating processes, the concentration of organic matter in desulfurized wastewater is generally 250-1500 mg / L (calculated as COD). If the organic matter is not effectively removed during pretreatment, it will be intercepted and enriched in the concentrated water during the membrane concentration stage. These organic matters are recycled through the concentrated water and continuously accumulate in the system, which will cause serious membrane fouling and frequent chemical cleaning, shorten the membrane life, and limit the efficient operation of the membrane system.

[0004] Polypropylene fiber has a high specific surface area, excellent physical and mechanical properties, and chemical properties, and is suitable for making the matrix of adsorption fibers. However, the adsorption capacity of polypropylene fiber for organic pollutants in desulfurized wastewater is poor, so it cannot effectively remove the organic pollutants in desulfurized wastewater.

[0005] Therefore, there is an urgent need to provide an adsorption material that can effectively remove organic pollutants in desulfurized wastewater. Summary of the Invention

[0006] The purpose of the present invention is to provide an adsorption material for desulfurized wastewater and a preparation method thereof. The adsorption material provided by the present invention can effectively remove organic pollutants in desulfurized wastewater.

[0007] In order to achieve the above invention purpose, the present invention provides the following technical solutions:

[0008] The present invention provides an adsorption material for desulfurized wastewater. The adsorption material for desulfurized wastewater is a non-woven fabric formed by modified fibers. The modified fibers include polypropylene fibers and methacrylic acid grafted onto the polypropylene fibers. The grafting rate of the methacrylic acid is 15-25%.

[0009] Preferably, the diameter of the modified fibers is 1-5 μm.

[0010] The present invention also provides a preparation method of the adsorption material for desulfurized wastewater according to the above technical solution, including the following steps:

[0011] (1) Mix polypropylene resin and a solvent, and carry out heating and swelling to obtain a polypropylene resin solution;

[0012] (2) Mix the polypropylene resin solution obtained in step (1) with an ice-water mixture to obtain a solution containing polypropylene resin particles;

[0013] (3) Mix the solution containing polypropylene resin particles obtained in step (2) with methacrylic acid monomer and an initiator, and carry out a grafting reaction to obtain a resin grafted with methacrylic acid;

[0014] (4) Carry out spinning on the resin grafted with methacrylic acid obtained in step (3) to obtain an adsorption material for desulfurized wastewater.

[0015] Preferably, the temperature of heating and swelling in step (1) is 145-155 °C.

[0016] Preferably, the time of heating and swelling is 0.1-0.5 h.

[0017] Preferably, the initiator in step (3) includes one or more of benzoyl peroxide, lauroyl peroxide, bis(2-phenoxyethyl) peroxydicarbonate, bis(2-ethylhexyl) peroxydicarbonate, and dicyclohexyl peroxydicarbonate.

[0018] Preferably, the temperature of the grafting reaction in step (3) is 60-95 °C.

[0019] Preferably, the time of the grafting reaction is 2-3 h.

[0020] Preferably, the mass ratio of the polypropylene resin, the solvent in step (1), the ice-water mixture in step (2), the methacrylic acid monomer and the initiator in step (3) is 1:(1-4):(5-12):(0.3-0.6):(0.01-0.02).

[0021] Preferably, the spinning method in step (4) is meltblown spinning.

[0022] The present invention provides an adsorbent material for desulfurized wastewater. The adsorbent material for desulfurized wastewater is a non-woven fabric formed by modified fibers. The modified fibers include polypropylene fibers and methacrylic acid grafted onto the polypropylene fibers. The grafting rate of the methacrylic acid is 15-25%. The adsorbent material for desulfurized wastewater provided by the present invention is a non-woven fabric formed by modified fibers. Using inexpensive and readily available polypropylene resin as the main raw material, methacrylic acid is grafted, and it has a high grafting rate. It can be used for the purification of organic pollutants in desulfurized wastewater during pretreatment. Its adsorption treatment effect is good, and it is basically not affected by temperature. The adsorption fiber has excellent regeneration performance, which is beneficial to ensuring the efficient operation of the membrane system. The results of the examples show that the removal rate of organic matter in desulfurized wastewater by commercially available polypropylene fibers is 56.42%, while the removal rate of organic matter in desulfurized wastewater by the adsorbent material for desulfurized wastewater provided by the present invention reaches more than 93%, and it can efficiently remove the organic matter in desulfurized wastewater. Detailed implementation mode

[0023] The present invention provides an adsorbent material for desulfurized wastewater. The adsorbent material for desulfurized wastewater is a non-woven fabric formed by modified fibers. The modified fibers include polypropylene fibers and methacrylic acid grafted onto the polypropylene fibers. The grafting rate of the methacrylic acid is 15-25%.

[0024] The adsorbent material for desulfurized wastewater provided by the present invention is a non-woven fabric formed by modified fibers. The present invention has no special limitation on the thickness of the non-woven fabric, and it can be adjusted according to needs.

[0025] In the present invention, the modified fibers include polypropylene fibers and methacrylic acid grafted onto the polypropylene fibers. By using polypropylene resin as the main raw material, the formed polypropylene fibers have excellent physical and mechanical properties and chemical properties, and are suitable for the matrix fibers of the adsorbent material for desulfurized wastewater.

[0026] In the present invention, the modified fibers include methacrylic acid grafted onto the polypropylene fibers. In the present invention, the grafting rate of the methacrylic acid is 15-25%, preferably 20-25%. By grafting methacrylic acid onto the polypropylene fibers in the present invention, the adsorption capacity for organic matter in wastewater can be greatly improved, thereby solving the problem that the adsorption capacity of polypropylene fibers for organic matter in wastewater is limited.

[0027] In the present invention, the diameter of the modified fibers is preferably 1-5 μm, more preferably 1-3 μm. The diameter of the modified fibers provided by the present invention is within the above range, which has a large specific surface area, increases the contact probability between the modified fibers and organic pollutants, and further improves the removal effect of organic matter in desulfurized wastewater.

[0028] The desulfurized wastewater adsorption material provided by the present invention grafts methacrylic acid onto polypropylene fibers and has a high grafting rate. It can be used as a pretreatment for purifying organic pollutants in desulfurized wastewater. Its adsorption treatment effect is good, and it is basically not affected by temperature. The adsorption fiber has excellent regeneration performance.

[0029] The present invention also provides a preparation method of the desulfurized wastewater adsorption material described in the above technical solution, including the following steps:

[0030] (1) Mix polypropylene resin and a solvent, and heat and swell to obtain a polypropylene resin solution;

[0031] (2) Mix the polypropylene resin solution obtained in step (1) with an ice-water mixture to obtain a solution containing polypropylene resin particles;

[0032] (3) Mix the solution containing polypropylene resin particles obtained in step (2) with methacrylic acid monomer and an initiator, and carry out a grafting reaction to obtain a resin grafted with methacrylic acid;

[0033] (4) Spin the resin grafted with methacrylic acid obtained in step (3) to obtain a desulfurized wastewater adsorption material.

[0034] The present invention mixes polypropylene resin and a solvent, and heats and swells to obtain a polypropylene resin solution.

[0035] The present invention has no special limitation on the source of the polypropylene resin, and conventional commercially available products can be used.

[0036] In the present invention, the solvent preferably includes one or more of xylene, toluene, n-heptane, phenol, decalin, and tetralin, and more preferably xylene. The present invention uses the solvent to fully swell the polypropylene resin, which is more conducive to subsequent grafting and spinning into fibers.

[0037] The present invention has no special limitation on the method of mixing the polypropylene resin and the solvent, as long as the two can be mixed evenly. In the present invention, the method of mixing the polypropylene resin and the solvent is preferably stirring, and the rotation speed of the stirring is preferably 100 - 300 r / min, more preferably 200 - 300 r / min.

[0038] In the present invention, the temperature of the heat swelling is preferably 145 - 155 °C, more preferably 150 - 155 °C; the time of the heat swelling is preferably 0.1 - 0.5 h, more preferably 0.2 - 0.5 h. In the present invention, the heat swelling is preferably carried out under stirring, and the rotation speed of the stirring is preferably 100 - 300 r / min, more preferably 200 - 300 r / min. The present invention can promote the polypropylene resin to fully swell in the solvent under the above conditions to form a polypropylene resin solution.

[0039] After obtaining the polypropylene resin solution, the present invention mixes the polypropylene resin solution with an ice-water mixture to obtain a solution containing polypropylene resin particles.

[0040] In the present invention, the ice-water mixture can rapidly reduce the temperature of the polypropylene resin solution, accelerate and change the crystallization process of polypropylene, change the crystal form of polypropylene, and form a solution containing polypropylene resin particles, which is beneficial to improving the grafting rate of the subsequent grafting reaction; moreover, after the ice-water mixture turns into water, it participates in the grafting reaction as one of the raw materials for the next reaction.

[0041] In the present invention, the method of mixing the polypropylene resin solution with the ice-water mixture is preferably stirring, and the rotation speed of the stirring is preferably 500-700 r / min, more preferably 600-700 r / min. The present invention has no special limitation on the mixing time, and it is sufficient to cool the temperature of the polypropylene resin solution to 60-95 °C.

[0042] After obtaining the solution containing polypropylene resin particles, the present invention mixes the solution containing polypropylene resin particles with methacrylic acid monomer and initiator to carry out a grafting reaction to obtain a resin grafted with methacrylic acid.

[0043] In the present invention, the initiator preferably includes one or more of benzoyl peroxide, lauroyl peroxide, bis(2-phenoxyethyl) peroxydicarbonate, bis(2-ethylhexyl) peroxydicarbonate, and dicyclohexyl peroxydicarbonate, and more preferably benzoyl peroxide. The present invention promotes the smooth progress of the grafting reaction by using the initiator.

[0044] In the present invention, the mass ratio of the polypropylene resin, solvent, ice-water mixture, methacrylic acid monomer, and initiator is preferably 1:(1-4):(5-12):(0.3-0.6):(0.01-0.02), and more preferably 1:(2-3):(8-10):(0.5-0.6):(0.015-0.02). The present invention controls the dosage of each component within the above range, which is more conducive to promoting the full progress of the grafting reaction.

[0045] In the present invention, the temperature of the grafting reaction is preferably 60-95 °C, more preferably 90 °C; the time of the grafting reaction is preferably 2-3 h, more preferably 2.5-3 h. Under the above temperature and time, the present invention is more conducive to promoting the full progress of the grafting reaction.

[0046] Preferably after the grafting reaction, the product obtained from the grafting reaction is centrifuged and dried in sequence to obtain a resin grafted with methacrylic acid. The present invention has no special limitation on the methods of centrifugation and drying. By using conventional methods of centrifugation and drying, solid-liquid separation can be fully achieved, and the solvent and water in the resin grafted with methacrylic acid can be fully removed. In the examples of the present invention, the drying temperature can be 90 °C.

[0047] After obtaining the resin grafted with methacrylic acid, the present invention spins the resin grafted with methacrylic acid to obtain a desulfurized wastewater adsorption material.

[0048] In the present invention, the spinning method is preferably meltblown spinning. The parameters of the meltblown spinning preferably include: the temperature of the first zone of the meltblown spinning machine screw is preferably 160 ± 5 °C, more preferably 160 °C; the temperature of the second zone of the meltblown spinning machine screw is preferably 200 ± 5 °C, more preferably 200 °C; the temperature of the third zone of the meltblown spinning machine screw is preferably 230 ± 5 °C, more preferably 230 °C; the temperatures of the metering pump zone and the flow channel zone are independently preferably 270 ± 5 °C, more preferably 270 °C; the temperature of the die head air heating zone is preferably 300 ± 5 °C, more preferably 300 °C; the air pressure gauge is preferably adjusted to 40 - 50 Hz, more preferably 45 Hz; the metering pump speed is preferably 10 - 12 rpm, more preferably 10 rpm; the hot air temperature is preferably 330 - 350 °C, more preferably 330 °C; the receiving distance is preferably 32 - 35 cm, more preferably 32 cm. By using meltblown spinning in the present invention, the modified fibers can have structural advantages such as small diameter and large specific surface area, which can increase the contact probability between the non-woven fabric formed by the modified fibers and the pollutants.

[0049] The present invention adjusts the temperature of the polypropylene resin solution by mixing the polypropylene resin solution with an ice-water mixture. After stabilizing the temperature, the monomer methacrylic acid and the initiator benzoyl peroxide are added for suspension grafting reaction, which can significantly improve the grafting rate of methacrylic acid, and further improve the adsorption capacity of the desulfurized wastewater adsorption material for organic pollutants in the desulfurized wastewater. At the same time, in the method provided by the present invention, methacrylic acid is firmly combined with the polypropylene fiber, enabling the adsorption material to have excellent regeneration performance.

[0050] Next, the technical solutions in the present invention will be clearly and completely described in conjunction with the examples in the present invention. Obviously, the described examples are only a part of the examples of the present invention, rather than all the examples. Based on the examples in the present invention, all other examples obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0051] Example 1

[0052] A desulfurized wastewater adsorption material, wherein the desulfurized wastewater adsorption material is a non-woven fabric formed by modified fibers, and the modified fibers are polypropylene fibers and methacrylic acid grafted on the polypropylene fibers; the grafting rate of the methacrylic acid is 20.30%; the average diameter of the modified fibers is 3 μm;

[0053] The preparation method of the desulfurized wastewater adsorption material is as follows:

[0054] (1) Add 100 g of polypropylene resin and 200 g of xylene into a reaction kettle with stirring, stir and heat up to 155 °C at 200 r / min, and keep it for 0.5 h for heat swelling to obtain a polypropylene resin solution;

[0055] (2) Stir the polypropylene resin solution obtained in step (1) with 1000 g of ice-water mixture at 600 r / min until the temperature reaches 90 °C to obtain a solution containing polypropylene resin particles;

[0056] (3) Mix the solution containing polypropylene resin particles obtained in step (2) with 50 g of methacrylic acid monomer and 2 g of initiator benzoyl peroxide, carry out suspension grafting reaction at 90 °C for 3 h, then centrifuge the product of the grafting reaction and dry it at 90 °C to obtain a resin grafted with methacrylic acid;

[0057] (4) Carry out meltblown spinning on the resin grafted with methacrylic acid obtained in step (3), and the parameters are: the temperature of the first zone of the screw of the meltblown spinning machine is 160 °C; the temperature of the second zone is 200 °C; the temperature of the third zone is 230 °C; the temperatures of the metering pump zone and the runner zone are independently 270 °C; the temperature of the die head air heating zone is 300 °C; the air pressure gauge is adjusted to 45 Hz; the metering pump speed is 10 rpm; the hot air temperature is 330 °C; the receiving distance is 32 cm; to obtain a desulfurized wastewater adsorption material, and the grafting rate of methacrylic acid is 20.30% after testing.

[0058] Example 2

[0059] A desulfurized wastewater adsorption material, wherein the desulfurized wastewater adsorption material is a non-woven fabric formed by modified fibers, and the modified fibers are polypropylene fibers and methacrylic acid grafted on the polypropylene fibers; the grafting rate of the methacrylic acid is 23.70%; the average diameter of the modified fibers is 2 μm;

[0060] The preparation method of the desulfurized wastewater adsorption material is as follows:

[0061] (1) Add 100 g of polypropylene resin and 300 g of xylene into a reaction kettle with stirring, stir and heat up to 150 °C at 300 r / min, and keep it for 0.2 h for heat swelling to obtain a polypropylene resin solution;

[0062] (2) Stir the polypropylene resin solution obtained in step (1) with 800 g of ice-water mixture at 700 r / min until the temperature reaches 90 °C to obtain a solution containing polypropylene resin particles.

[0063] (3) Mix the solution containing polypropylene resin particles obtained in step (2) with 60 g of methyl methacrylate monomer and 2 g of initiator benzoyl peroxide, and carry out suspension grafting reaction at 90 °C for 2.5 h. Then, centrifuge the product of the grafting reaction and dry it at 90 °C to obtain the resin grafted with methyl methacrylate.

[0064] (4) Carry out meltblown spinning on the resin grafted with methyl methacrylate obtained in step (3). The parameters are as follows: the temperature of the first zone of the screw of the meltblown spinning machine is 160 °C; the temperature of the second zone is 200 °C; the temperature of the third zone is 230 °C; the temperatures of the metering pump zone and the flow channel zone are independently 270 °C; the temperature of the die head air heating zone is 300 °C; the air pressure gauge is adjusted to 45 Hz; the rotational speed of the metering pump is 10 rpm; the temperature of the hot air is 330 °C; the receiving distance is 32 cm. Obtain the desulfurized wastewater adsorption material, and the grafting rate of methyl methacrylate is measured to be 23.70%.

[0065] Comparative Example 1

[0066] Purchase commercial polypropylene fiber as the adsorption material, and the measured grafting rate is 0%.

[0067] Comparative Example 2

[0068] A desulfurized wastewater adsorption material, wherein the desulfurized wastewater adsorption material is a non-woven fabric formed by modified fibers. The modified fibers are polypropylene fibers and methyl methacrylate grafted on the polypropylene fibers; the grafting rate of the methyl methacrylate is 11.30%; the average diameter of the modified fibers is 4 μm.

[0069] The preparation method of the desulfurized wastewater adsorption material is as follows:

[0070] (1) Add 100 g of polypropylene resin and 300 g of xylene into a reaction kettle with stirring, stir and heat up to 150 °C at 300 r / min, and keep it for 0.2 h for heating and swelling to obtain a polypropylene resin solution.

[0071] (2) Naturally cool the polypropylene resin solution obtained in step (1) to 90 °C, and then stir and mix it with 800 g of water at 90 °C to obtain a solution containing polypropylene resin particles.

[0072] (3) Mix the solution containing polypropylene resin particles obtained in step (2) with 60 g of methacrylic acid monomer and 2 g of initiator benzoyl peroxide, carry out suspension grafting reaction at 90 °C for 2.5 h, then centrifuge the product of the grafting reaction and dry it at 90 °C to obtain resin grafted with methacrylic acid;

[0073] (4) Carry out meltblown spinning on the resin grafted with methacrylic acid obtained in step (3), and the parameters are as follows: the temperature of the first zone of the screw of the meltblown spinning machine is 160 °C; the temperature of the second zone is 200 °C; the temperature of the third zone is 230 °C; the temperatures of the metering pump zone and the flow channel zone are independently 270 °C; the temperature of the die head air heating zone is 300 °C; the air pressure gauge is adjusted to 45 Hz; the rotational speed of the metering pump is 10 rpm; the temperature of the hot air is 330 °C; the receiving distance is 32 cm; to obtain modified fibers, and the grafting rate of methacrylic acid is measured to be 11.30%.

[0074] Test Example 1

[0075] (1) Conduct adsorption performance tests on the desulfurized wastewater adsorption materials obtained in Examples 1-2 and Comparative Examples 1-2, and the test method is as follows: Take 0.5 g of different adsorption materials and place them in 500 mL of thermal power plant desulfurized wastewater (the measured initial COD is 358 mg / L) for the adsorption of organic matter. After 180 min of adsorption, take the supernatant to measure COD, and calculate the removal rate of COD in the desulfurized wastewater by different fiber adsorption materials. The results are shown in Table 1 below.

[0076] Table 1 Test results of the adsorption performance of different desulfurized wastewater adsorption materials

[0077] Project Example 1 Example 2 Comparative Example 1 Comparative Example 2 COD after adsorption (mg / L) 23 17 156 78 COD removal rate (%) 93.58 95.25 56.42 78.21

[0078] As can be seen from Table 1, the adsorption materials prepared in Examples 1-2 have strong adsorption ability for organic matter in desulfurized wastewater, and the COD removal effect is obvious. Comparative Example 1 shows that although commercial polypropylene fibers have a certain adsorption ability, the functional groups of the grafted monomer increase the contact probability between the adsorption material and the organic matter in the desulfurized wastewater, enhancing the adsorption effect. Comparative Example 2 shows that after treatment with an ice-water mixture, the grafting rate is increased, that is, the number of functional groups of the grafted monomer is increased, strengthening the adsorption effect of the adsorption material.

[0079] (2) Take 0.5 g of the desulfurized wastewater adsorption material in Example 2 and place it in 500 mL of thermal power plant desulfurized wastewater for the adsorption of organic matter. Change the temperature of the desulfurized wastewater, and the adsorption time is 180 min. Calculate the removal rate of COD in the desulfurized wastewater by the adsorption material at different temperatures according to the change of COD before and after adsorption. The results are shown in Table 2 below.

[0080] Table 2 Influence results of different temperatures on the COD removal rate of the desulfurized wastewater adsorption material

[0081] Project 35℃ 45℃ 55℃ 65℃ 75℃ COD removal rate (%) 95.25 95.27 95.15 94.96 94.39

[0082] As can be seen from Table 2, when the desulfurized wastewater adsorption material prepared by the present invention is used for removing organic matter in desulfurized wastewater, it is basically not affected by temperature. This shows that the desulfurized wastewater adsorption material prepared by the present invention has excellent high-temperature stability and can be applied to the treatment of desulfurized wastewater at different temperatures.

[0083] (3) The desulfurized wastewater adsorption material prepared in Example 2 was saturated with adsorption, and then the saturated desulfurized wastewater adsorption material was desorbed and regenerated in a 0.5 mol / L HCl solution. Then, the desorbed desulfurized wastewater adsorption material was used to adsorb the wastewater again to investigate the change in its regeneration adsorption effect. The results are shown in Table 3 below.

[0084] Table 3 Test results of the regeneration performance of the desulfurized wastewater adsorption material

[0085] Project COD removal rate (%) Regeneration 1 time 95.22 Regeneration 2 times 95.13 Regeneration 3 times 94.82 Regeneration 4 times 93.76 Regeneration 5 times 91.92 Regeneration 6 times 90.69

[0086] As can be seen from Table 3, with the increase in the number of regeneration times of the adsorption material, the removal rate of COD in desulfurized wastewater decreases slightly. After 6 regenerations, the COD removal rate can still reach more than 90%. Thus, it can be seen that the fiber adsorption material of the present invention has excellent desorption regeneration and reusability, and has excellent stability.

[0087] The desulfurized wastewater adsorption material provided by the present invention has a high grafting rate of methacrylic acid. As a pretreatment for purifying organic pollutants in desulfurized wastewater, it has good adsorption treatment effect, is basically not affected by temperature, and has excellent regeneration performance of the adsorption fiber, which is beneficial to ensuring the efficient operation of the membrane system and facilitating the zero discharge of desulfurized wastewater from thermal power plants.

[0088] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A desulfurization wastewater adsorbent material, which is a non-woven fabric formed by modified fibers, wherein the modified fibers include polypropylene fibers and methacrylic acid grafted onto the polypropylene fibers; the grafting rate of the methacrylic acid is 15-25%.

2. The desulfurization wastewater adsorption material according to claim 1, characterized in that: The diameter of the modified fiber is 1 to 5 μm.

3. The method for preparing the desulfurization wastewater adsorbent according to claim 1, comprising the following steps: (1) mixing a polypropylene resin and a solvent, and heating and swelling the mixture to obtain a polypropylene resin solution; (2) mixing the polypropylene resin solution obtained in step (1) with an ice-water mixture to obtain a solution containing polypropylene resin particles; (3) mixing the solution containing the polypropylene resin particles obtained in step (2) with methacrylic acid monomer and an initiator to carry out a grafting reaction to obtain a resin grafted with methacrylic acid; (4) Spinning the resin grafted with methacrylic acid obtained in step (3) to obtain a desulfurization wastewater adsorbent material.

4. The preparation method according to claim 3, characterized in that: The temperature for heating and swelling in step (1) is 145-155°C.

5. The preparation method according to claim 3 or 4, characterized in that: The heating and swelling time is 0.1 to 0.5 h.

6. The preparation method according to claim 3, characterized in that: The initiator in step (3) includes one or more of benzoyl peroxide, lauroyl peroxide, di(2-phenoxyethyl) peroxydicarbonate, di(2-ethylhexyl) peroxydicarbonate and dicyclohexyl peroxydicarbonate.

7. The preparation method according to claim 3, characterized in that: The temperature of the grafting reaction in step (3) is 60-95°C.

8. The preparation method according to claim 3 or 7, characterized in that: The grafting reaction time is 2 to 3 hours.

9. The preparation method according to claim 3, characterized in that: The mass ratio of the polypropylene resin in step (1), the solvent, the ice-water mixture in step (2), the methacrylic acid monomer in step (3) and the initiator is 1: (1-4): (5-12): (0.3-0.6): (0.01-0.02).

10. The preparation method according to claim 3, characterized in that: The spinning method in step (4) is melt-blown spinning.