Flocculating agent doped with magnetic cellulose and preparation method thereof

Abstract

The invention belongs to the technical field of environmental treatment, and particularly relates to a magnetic cellulose doped flocculant which is characterized by comprising the following substances in parts by weight: 5-10 parts of acrylamide, 35-40 parts of acrylic acid, 8-10 parts of magnetic cellulose, 3-6 parts of an initiator and 5-8 parts of chitosan. The magnetic cellulose-doped flocculant prepared by the invention has strong COD (Chemical Oxygen Demand) and TSS (Total Suspended Solids) removal effects, can remarkably reduce the chroma and turbidity of wastewater, effectively reduces the use of traditional chemical flocculants, reduces the risk of secondary pollution, can be recycled, and is safe and environment-friendly.

Description

Technical Field

[0001] The present invention belongs to the technical field of environmental treatment, and particularly relates to a flocculant doped with magnetic cellulose and a preparation method thereof. Background Art

[0002] With the development of industrialization, the components of pollutants in wastewater are becoming increasingly complex. The problems of exceeding the standards of chemical oxygen demand (COD), total suspended solids (TSS), turbidity and chromaticity pose great challenges to traditional wastewater treatment methods. Existing technologies such as chemical flocculants (such as PAC) and biological flocculants can solve the pollution problem to a certain extent, but generally have problems such as low treatment efficiency, complex operating conditions, high treatment cost and possible secondary pollution to the environment. Summary of the Invention

[0003] The purpose of the present invention is to address the existing problems and provide a flocculant doped with magnetic cellulose and a preparation method thereof.

[0004] The present invention is achieved through the following technical solutions:

[0005] A flocculant doped with magnetic cellulose, comprising the following substances in corresponding parts by weight:

[0006] 5-10 parts of acrylamide, 35-40 parts of acrylic acid, 8-10 parts of magnetic cellulose, 3-6 parts of initiator, 5-8 parts of chitosan.

[0007] Further, the preparation method of the magnetic cellulose comprises the following steps:

[0008] (1) Mix cellulose, nano-titanium dioxide and a coupling agent together and add them to distilled water. After ultrasonic treatment for 20-30 min, add FeCl2 and FeCl3, then add ammonia water and stir to adjust the overall pH value to 8-9. After heating and reacting for 2-3 h, add sodium alginate;

[0009] (2) Transfer them together to a reaction kettle for heating and reaction treatment for 10-12 h, filter and wash the solid product, and finally perform a drying treatment.

[0010] Further, the cellulose in step (1) is microcrystalline cellulose; the particle size of the nano-titanium dioxide is not more than 20 nm; the coupling agent is a silane coupling agent.

[0011] Further, the mass ratio of the cellulose, nano-titanium dioxide, coupling agent, FeCl2, FeCl3 and sodium alginate is: 25-28: 0.1-0.2: 0.5-1: 1: 1-1.5: 6-8.

[0012] Further, the frequency of the ultrasonic treatment in step (1) is 80 - 100 kHz; the overall temperature is controlled at 60 - 80 °C during the heating reaction.

[0013] Further, the temperature in the reaction kettle is controlled at 145 - 155 °C during the heating reaction treatment in step (2); the drying temperature is controlled at 80 - 90 °C during the drying treatment.

[0014] A preparation method of a flocculant doped with magnetic cellulose, comprising the following steps:

[0015] S1. Put acrylamide, acrylic acid, and magnetic cellulose into a reaction kettle filled with distilled water, stir evenly, add an initiator, and stir and react for 8 - 10 h;

[0016] S2. Then add chitosan and heat up to react for 4 - 6 h, and finally filter, wash the solid product, and dry it.

[0017] Further, the initiator in step S1 is potassium persulfate; the temperature in the reaction kettle is controlled at 6 - 10 °C during the stirring and reaction treatment.

[0018] Further, the temperature in the reaction kettle is controlled at 35 - 45 °C during the heating reaction treatment in step S2.

[0019] The present invention has the following advantages compared with the prior art:

[0020] 1. The present invention provides a flocculant doped with magnetic cellulose, in which magnetic cellulose components are added and used. This component is actually cellulose particles modified by nano-ferroferric oxide. On the one hand, it has magnetism and is conducive to recycling, and on the other hand, it can significantly enhance the complexation and adsorption effects on heavy metals, suspended solids, etc. The nano-titanium dioxide added during its preparation is conducive to the reaction and attachment of ferroferric oxide in the initial stage, and can further improve the structure of the finished product particles, enhance its specific surface area, and enhance the adsorption effect; in addition, chitosan components are used in combination. While enhancing its hydrophilicity, it is also conducive to degradation and recycling, and has a synergistic enhancement effect on the flocculation effect.

[0021] 2. The flocculant doped with magnetic cellulose prepared by the present invention has a strong COD and TSS removal effect, can significantly reduce the chromaticity and turbidity of wastewater, effectively reduce the use of traditional chemical flocculants, reduce the risk of secondary pollution, and can also be recycled, which is safe and environmentally friendly. Specific Embodiments

[0022] In order to further explain the present invention, the following specific embodiments are described below.

[0023] Example 1

[0024] A flocculant doped with magnetic cellulose, comprising the following substances in corresponding parts by weight:

[0025] 5 parts of acrylamide, 35 parts of acrylic acid, 8 parts of magnetic cellulose, 3 parts of initiator, 5 parts of chitosan.

[0026] The preparation method of magnetic cellulose comprises the following steps:

[0027] (1) Mix cellulose, nano-titanium dioxide and coupling agent together and add them into distilled water. Control the frequency of ultrasonic treatment at 80 kHz. After ultrasonic treatment for 20 min, add FeCl2 and FeCl3; then add ammonia water and stir to adjust the overall pH value to 8, heat to 60 °C, react for 2 h and then add sodium alginate; the mass ratio of cellulose, nano-titanium dioxide, coupling agent, FeCl2, FeCl3 and sodium alginate is: 25:0.1:0.5:1:1:6;

[0028] (2) Transfer them together into a reaction kettle and heat. Control the temperature in the reaction kettle at 145 °C, react for 10 h, filter and wash the solid product, and finally perform hot air drying treatment at 80 °C.

[0029] The cellulose described in step (1) of this example is microcrystalline cellulose; the particle size of nano-titanium dioxide is not more than 20 nm; the coupling agent is a silane coupling agent, specifically kh550 silane coupling agent. In actual preparation, the particle size of nano-titanium dioxide should not be too large, as it will affect the attachment of magnetite and reduce or even bring negative synergistic effects; the addition of the coupling agent here can promote the dispersion of nano-titanium dioxide, improve its affinity with cellulose, and enhance the attachment effect of magnetite at the same time;

[0030] A preparation method of a flocculant doped with magnetic cellulose, comprising the following steps:

[0031] Put acrylamide, acrylic acid and magnetic cellulose into a reaction kettle containing distilled water according to parts by weight. The input amount of distilled water can be excessive to ensure the complete dissolution of the solute. After stirring evenly, add the initiator. The initiator is selected as potassium persulfate. Control the temperature in the reaction kettle at 6 °C and stir and react for 8 h; then add chitosan, and then raise the temperature to control the temperature in the reaction kettle at 35 °C and react for 4 h. Finally, filter, wash the solid product and dry it.

[0032] Example 2

[0033] A flocculant doped with magnetic cellulose, comprising the following substances in corresponding parts by weight:

[0034] 5 parts of acrylamide, 38 parts of acrylic acid, 9 parts of magnetic cellulose, 3 parts of initiator, 5 parts of chitosan.

[0035] The preparation method of magnetic cellulose includes the following steps:

[0036] (1) Mix cellulose, nano-titanium dioxide and coupling agent together and add them into distilled water. Control the frequency of ultrasonic treatment at 80 kHz. After ultrasonic treatment for 20 min, add FeCl2 and FeCl3; then add ammonia water and stir to adjust the overall pH value to 8, heat to 60 °C, react for 2.5 h and then add sodium alginate; the mass ratio of cellulose, nano-titanium dioxide, coupling agent, FeCl2, FeCl3 and sodium alginate is: 27:0.15:0.5:1:1:6;

[0037] (2) Transfer them together into a reaction kettle and heat. Control the temperature in the reaction kettle at 150 °C, react for 10 - 12 h, filter and wash the solid product, and finally perform hot air drying treatment at 85 °C.

[0038] In step (1) of this example, the cellulose mentioned is microcrystalline cellulose; the particle size of nano-titanium dioxide is not more than 20 nm; the coupling agent is a silane coupling agent, specifically kh550 silane coupling agent. During actual preparation, the particle size of nano-titanium dioxide should not be too large, as it will affect the attachment of magnetite and reduce or even bring negative synergistic effects; the addition of the coupling agent here can promote the dispersion of nano-titanium dioxide, improve its affinity with cellulose, and enhance the attachment effect of magnetite at the same time;

[0039] The preparation method of a flocculant doped with magnetic cellulose includes the following steps:

[0040] Put acrylamide, acrylic acid and magnetic cellulose into a reaction kettle containing distilled water by weight. The input amount of distilled water can be excessive to ensure the complete dissolution of solutes. After stirring evenly, add an initiator, and the initiator is selected as potassium persulfate. Control the temperature in the reaction kettle at 6 °C and stir and react for 8 h; then add chitosan, and then raise the temperature to control the temperature in the reaction kettle at 35 °C and react for 4 h. Finally, filter and wash the solid product and dry it.

[0041] Example 3

[0042] A flocculant doped with magnetic cellulose includes the following substances in corresponding parts by weight:

[0043] 8 parts of acrylamide, 37 parts of acrylic acid, 9 parts of magnetic cellulose, 5 parts of initiator, 7 parts of chitosan.

[0044] The preparation method of magnetic cellulose includes the following steps:

[0045] (1) Mix cellulose, nano-titanium dioxide and coupling agent together and add them to distilled water. Control the frequency of ultrasonic treatment at 90 kHz. After ultrasonic treatment for 25 min, add FeCl2 and FeCl3; then add ammonia water and stir to adjust the overall pH value to 8.5, heat to 65 °C, react for 2.5 h and then add sodium alginate; the mass ratio of cellulose, nano-titanium dioxide, coupling agent, FeCl2, FeCl3 and sodium alginate is: 27:0.15:0.8:1:1.2:7;

[0046] (2) Transfer them together to a reaction kettle and heat. Control the temperature in the reaction kettle at 150 °C, react for 11 h, filter and wash the solid product, and finally dry it by hot air drying at 85 °C.

[0047] The cellulose mentioned in step (1) of this example is microcrystalline cellulose; the particle size of nano-titanium dioxide is not more than 20 nm; the coupling agent is a silane coupling agent, specifically kh550 silane coupling agent. In actual preparation, the particle size of nano-titanium dioxide should not be too large, otherwise it will affect the adhesion of magnetite and reduce or even bring negative synergistic effects; the addition of the coupling agent here can promote the dispersion of nano-titanium dioxide, improve its affinity with cellulose, and enhance the adhesion effect of magnetite at the same time;

[0048] A preparation method of a flocculant doped with magnetic cellulose includes the following steps:

[0049] Put acrylamide, acrylic acid and magnetic cellulose into a reaction kettle containing distilled water by weight. The input amount of distilled water can be excessive to ensure the complete dissolution of the solute. After stirring evenly, add an initiator, and the initiator is selected as potassium persulfate. Control the temperature in the reaction kettle at 8 °C and stir and react for 9 h; then add chitosan, and then raise the temperature to control the temperature in the reaction kettle at 40 °C and react for 5 h. Finally, filter, wash the solid product and dry it.

[0050] Example 4

[0051] A flocculant doped with magnetic cellulose includes the following substances in corresponding parts by weight:

[0052] 10 parts of acrylamide, 40 parts of acrylic acid, 9 parts of magnetic cellulose, 5 parts of initiator, 6 parts of chitosan.

[0053] The preparation method of magnetic cellulose includes the following steps:

[0054] (1) Mix cellulose, nano-titanium dioxide, and coupling agent together and add them to distilled water. Control the frequency of ultrasonic treatment at 90 kHz. After ultrasonic treatment for 25 min, add FeCl2 and FeCl3; then add ammonia water and stir to adjust the overall pH value to 9, heat to 80 °C, react for 3 h, and then add sodium alginate; the mass ratio of cellulose, nano-titanium dioxide, coupling agent, FeCl2, FeCl3, and sodium alginate is: 27:0.2:1:1:1.5:8;

[0055] (2) Transfer them together to a reaction kettle and heat. Control the temperature in the reaction kettle at 155 °C, react for 12 h, filter and wash the solid product, and finally perform hot air drying treatment at 90 °C.

[0056] The cellulose described in step (1) of this example is microcrystalline cellulose; the particle size of nano-titanium dioxide is not greater than 20 nm; the coupling agent is a silane coupling agent, specifically kh550 silane coupling agent. During actual preparation, the particle size of nano-titanium dioxide should not be too large, as it will affect the attachment of magnetite and reduce or even bring negative synergistic effects; the addition of the coupling agent here can promote the dispersion of nano-titanium dioxide, improve its affinity with cellulose, and enhance the attachment effect of magnetite at the same time;

[0057] A preparation method of a flocculant doped with magnetic cellulose includes the following steps:

[0058] Put acrylamide, acrylic acid, and magnetic cellulose into a reaction kettle containing distilled water by weight. The input amount of distilled water can be excessive to ensure the complete dissolution of the solute. After stirring evenly, add an initiator, and the initiator is selected as potassium persulfate. Control the temperature in the reaction kettle at 10 °C and stir and react for 10 h; then add chitosan, and then raise the temperature to control the temperature in the reaction kettle at 45 °C, react for 5 h, and finally filter, wash the solid product, and dry it.

[0059] Example 5

[0060] A flocculant doped with magnetic cellulose includes the following substances in corresponding parts by weight:

[0061] 10 parts of acrylamide, 40 parts of acrylic acid, 10 parts of magnetic cellulose, 6 parts of initiator, 8 parts of chitosan.

[0062] The preparation method of magnetic cellulose includes the following steps:

[0063] (1) Mix cellulose, nano-titanium dioxide, and coupling agent together and add them to distilled water. Control the frequency of ultrasonic treatment at 100 kHz. After ultrasonic treatment for 30 min, add FeCl2 and FeCl3; then add ammonia water and stir to adjust the overall pH value to 9, heat to 80 °C, and react for 3 h before adding sodium alginate; the mass ratio of cellulose, nano-titanium dioxide, coupling agent, FeCl2, FeCl3, and sodium alginate is: 28:0.2:1:1:1.5:8;

[0064] (2) Transfer them together to a reaction kettle and heat, control the temperature in the reaction kettle at 155 °C, react for 12 h, filter and wash the solid product, and finally perform hot air drying treatment at 90 °C.

[0065] The cellulose described in step (1) of this example is microcrystalline cellulose; the particle size of nano-titanium dioxide is not greater than 20 nm; the coupling agent is a silane coupling agent, specifically kh550 silane coupling agent. During actual preparation, the particle size of nano-titanium dioxide should not be too large, as it will affect the attachment of magnetite, reducing or even bringing negative synergistic effects; the addition of the coupling agent here can promote the dispersion of nano-titanium dioxide, enhance its affinity with cellulose, and at the same time enhance the attachment effect of magnetite;

[0066] A preparation method of a flocculant doped with magnetic cellulose includes the following steps:

[0067] Put acrylamide, acrylic acid, and magnetic cellulose into a reaction kettle containing distilled water by weight. The input amount of distilled water can be excessive to ensure the complete dissolution of the solute. After stirring evenly, add an initiator, and the initiator is selected as potassium persulfate. Control the temperature in the reaction kettle at 10 °C and stir and react for 10 h; then add chitosan, and then raise the temperature to control the temperature in the reaction kettle at 45 °C and react for 6 h. Finally, filter, wash the solid product, and dry it.

[0068] Comparative Example 1

[0069] A flocculant doped with magnetic cellulose includes the following substances in corresponding parts by weight:

[0070] 8 parts of acrylamide, 37 parts of acrylic acid, 9 parts of magnetic cellulose, 5 parts of initiator, 7 parts of chitosan.

[0071] The preparation method of magnetic cellulose includes the following steps:

[0072] (1) Mix cellulose, nano-titanium dioxide, and coupling agent together and add them to distilled water. Control the frequency of ultrasonic treatment at 90 kHz. After ultrasonic treatment for 25 min, add FeCl2 and FeCl3; then add ammonia water and stir to adjust the overall pH value to 8.5, heat to 65 °C, react for 2.5 h, and then add sodium alginate; the mass ratio of cellulose, nano-titanium dioxide, coupling agent, FeCl2, FeCl3, and sodium alginate is: 27:0.15:0.8:1:1.2:7;

[0073] (2) Transfer them together to a reaction kettle and heat. Control the temperature in the reaction kettle at 150 °C, react for 11 h, filter and wash the solid product, and finally perform hot air drying treatment at 85 °C.

[0074] The cellulose described in step (1) of this example is microcrystalline cellulose; the particle size of nano-titanium dioxide is controlled at 80 - 100 nm; the coupling agent is a silane coupling agent, specifically kh550 silane coupling agent.

[0075] A preparation method of a flocculant doped with magnetic cellulose includes the following steps:

[0076] Put acrylamide, acrylic acid, and magnetic cellulose into a reaction kettle filled with distilled water by weight. The input amount of distilled water can be excessive to ensure the complete dissolution of the solute. After stirring evenly, add an initiator. The initiator is selected as potassium persulfate. Control the temperature in the reaction kettle at 8 °C and stir and react for 9 h; then add chitosan, and then raise the temperature to control the temperature in the reaction kettle at 40 °C and react for 5 h. Finally, filter and wash the solid product and dry it.

[0077] The difference between this comparative example 1 and example 3 is that the particle size of nano-titanium dioxide is adjusted to be larger, and the rest of the method steps are exactly the same.

[0078] Comparative Example 2

[0079] A flocculant doped with magnetic cellulose includes the following substances in corresponding parts by weight:

[0080] 8 parts of acrylamide, 37 parts of acrylic acid, 9 parts of magnetic cellulose, 5 parts of initiator, 7 parts of chitosan.

[0081] The preparation method of magnetic cellulose includes the following steps:

[0082] (1) Mix cellulose and coupling agent together and add them to distilled water. Control the frequency of ultrasonic treatment at 90 kHz. After ultrasonic treatment for 25 min, add FeCl2 and FeCl3; then add ammonia water and stir to adjust the overall pH value to 8.5, heat to 65 °C, and react for 2.5 h before adding sodium alginate; the mass ratio of cellulose, coupling agent, FeCl2, FeCl3, and sodium alginate is: 27:0.8:1:1.2:7;

[0083] (2) Transfer them together to a reaction kettle and heat. Control the temperature in the reaction kettle at 150 °C and react for 11 h. Filter and wash the solid product, and finally dry it by hot air drying at 85 °C.

[0084] The cellulose described in step (1) of this example is microcrystalline cellulose; the coupling agent is a silane coupling agent, specifically kh550 silane coupling agent.

[0085] A preparation method of a flocculant doped with magnetic cellulose includes the following steps:

[0086] Put acrylamide, acrylic acid, and magnetic cellulose into a reaction kettle containing distilled water by weight. The input amount of distilled water can be excessive to ensure the complete dissolution of the solute. After stirring evenly, add an initiator, and the initiator is selected as potassium persulfate. Control the temperature in the reaction kettle at 8 °C and stir and react for 9 h; then add chitosan, and then raise the temperature to control the temperature in the reaction kettle at 40 °C and react for 5 h. Finally, filter and wash the solid product and dry it.

[0087] The difference between this comparative example 2 and example 3 is that the component of nano-titanium dioxide is omitted, and the rest of the method steps are exactly the same.

[0088] Comparative Example 3

[0089] A flocculant doped with magnetic cellulose includes the following substances in corresponding parts by weight:

[0090] 8 parts of acrylamide, 37 parts of acrylic acid, 9 parts of microcrystalline cellulose, 5 parts of initiator, 7 parts of chitosan.

[0091] The difference between this comparative example 3 and example 3 is that microcrystalline cellulose is used to replace magnetic cellulose, and the rest of the method steps are exactly the same.

[0092] In order to compare the above treatment effects, sewage treatment experiments were carried out on the above examples. Specifically,

[0093] Treat the simulated wastewater treated by the composite treatment of diatomite solution. The water quality characteristics of the simulated wastewater are as follows: the COD concentration is 92.9 mg / L; the TN concentration is 22.5 mg / L; the TP concentration is 3.8 mg / L; then use the flocculant prepared in the above embodiment for dosing and decontamination, and finally detect the corresponding removal rate. The specific results are shown in Table 1 below, where the input mass ratio of the flocculant to the simulated wastewater is 1:500;

[0094] Table 1

[0095]

[0096]

[0097] It can be seen from this that the flocculant prepared by the present invention has a significant improvement in the effect of treating sewage.

[0098] The above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A flocculant doped with magnetic cellulose, characterized in that, It comprises the following substances in corresponding parts by weight: 5 - 10 parts of acrylamide, 35 - 40 parts of acrylic acid, 8 - 10 parts of magnetic cellulose, 3 - 6 parts of initiator, 5 - 8 parts of chitosan.

2. The flocculant doped with magnetic cellulose according to claim 1, wherein The preparation method of the magnetic cellulose comprises the following steps: (1) Mix cellulose, nano-titanium dioxide and coupling agent together and add them into distilled water. After ultrasonic treatment for 20 - 30 min, add FeCl2 and FeCl3, then add ammonia water and stir to adjust the overall pH value to 8 - 9. After heating and reacting for 2 - 3 h, add sodium alginate; (2) Transfer them together into a reaction kettle for heating and reacting for 10 - 12 h, filter and wash the solid product, and finally carry out drying treatment.

3. The flocculant doped with magnetic cellulose according to claim 2, characterized in that, The cellulose described in step (1) is microcrystalline cellulose; the particle size of the nano-titanium dioxide is not more than 20 nm; the coupling agent is a silane coupling agent.

4. A flocculant doped with magnetic cellulose according to claim 3, characterized in that, The mass ratio of the cellulose, nano-titanium dioxide, coupling agent, FeCl2, FeCl3 and sodium alginate is: 25 - 28: 0.1 - 0.2: 0.5 - 1: 1: 1 - 1.5: 6 - 8.

5. A flocculant doped with magnetic cellulose according to claim 4, characterized in that, The frequency of the ultrasonic treatment in step (1) is 80 - 100 kHz; the overall temperature is controlled at 60 - 80 °C during the heating reaction.

6. A flocculant doped with magnetic cellulose according to claim 5, characterized in that The temperature in the reaction kettle is controlled at 145 - 155 °C during the heating and reacting treatment in step (2); the drying temperature is controlled at 80 - 90 °C during the drying treatment.

7. A preparation method of a flocculant doped with magnetic cellulose according to any one of claims 1-6, characterized in that, It comprises the following steps: S1. Put acrylamide, acrylic acid and magnetic cellulose into a reaction kettle containing distilled water. After stirring evenly, add the initiator and stir and react for 8 - 10 h; S2. Then add chitosan and raise the temperature to react for 4 - 6 h. Finally, filter and wash the solid product and dry it.

8. The preparation method of a flocculant doped with magnetic cellulose according to claim 7, characterized in that, The initiator described in step S1 is potassium persulfate; the temperature in the reaction kettle is controlled at 6 - 10 °C during the stirring and reacting treatment.

9. The preparation method of a flocculant doped with magnetic cellulose according to claim 7, characterized in that, The temperature in the reaction kettle is controlled at 35 - 45 °C during the temperature-raising reaction treatment in step S2.

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