Phytic acid functionalized fly ash floating bead adsorption material as well as preparation method and application thereof
By combining phytic acid with fly ash float beads, phytic acid functional fly ash float bead adsorption material is prepared, which solves the problems of low efficiency and high cost of organic dye wastewater treatment in the prior art, and achieves an efficient and environmentally friendly dye removal effect.
Patent Information
- Application Number
- CN202510349712.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-24
- Publication Date
- 2025-05-09
AI Technical Summary
Existing adsorbent materials are inefficient and costly when dealing with organic dye wastewater, and the industrial by-product fly ash float beads are limited by moisture and trace organic groups in adsorbing organic dyes.
Phytic acid functionalized fly ash beads are prepared by mixing fly ash beads with phytic acid solution and performing ultrasonic uniformity and polycondensation reaction. This material enhances the adsorption effect on cationic dyes through electrostatic action.
The efficient removal rate of organic dyes is achieved, especially when processing 20mL of 100mg/L of dyes, the removal rate is achieved of no less than 90%, while reducing the pollution to the environment, and the raw material cost is low and the process is simple.
Smart Images
Figure CN119951462A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of adsorption materials and waste resource utilization, and specifically relates to a phytic acid functionalized fly ash floating bead adsorption material and a preparation method and application thereof, which are used for efficiently treating organic dyes. Background Art
[0002] At present, there are coagulation method, membrane separation method, adsorption method, advanced oxidation method, biological method, etc. Among these technologies, adsorption technology has low cost, high efficiency, no secondary pollution, and can be used in large-scale production.
[0003] Fly ash beads (FAC) are an industrial byproduct of thermal power plants. The main components of fly ash beads are SiO2, Al2O3, Fe2O3, etc. The beads have a smooth surface, thin walls and hollow, rich in hydroxyl groups (-OH) on the surface, and relatively abundant pores inside, which can be used as adsorption materials. However, since the beads contain an indefinite amount of water and trace amounts of organic groups, they are limited in their ability to adsorb organic dyes. Researchers have improved the adsorption capacity of fly ash beads for organic dyes by surface modification.
[0004] Phytic acid (PA) is a biological and environmentally friendly organic phosphide that is widely found in cereals, beans and plant seeds. There are six phosphate groups in the phytic acid molecular structure that can coordinate with metal ions in metal oxides, and it is easily soluble in water and has strong acidity. In addition, phytic acid contains 12 ionizable protons, which enhance the adsorption effect of cationic dyes through electrostatic interaction. Therefore, the present invention uses phytic acid to modify the surface of fly ash floating beads to prepare a phytic acid functionalized fly ash floating beads adsorption material, in order to develop an environmentally friendly adsorption material suitable for treating organic dye wastewater pollution. Summary of the invention
[0005] The purpose of the present invention is to provide a method for preparing an environmentally friendly, low-cost, high-adsorption-efficiency phytic acid functionalized fly ash floating beads (PA-FAC) adsorption material, which is applied to the treatment of organic dye wastewater pollution.
[0006] In order to achieve the above purpose, the technical solution adopted is:
[0007] A method for preparing a phytic acid functionalized fly ash floating bead adsorption material, characterized in that it comprises the following steps:
[0008] (1) Fly ash beads of different mesh sizes are sieved, washed and dried to obtain pretreated industrial waste.
[0009] (2) The industrial waste pretreated in (1) is mixed with the phytic acid solution in a certain mass ratio, and after being ultrasonically homogenized, the mixture is placed in an oven for polycondensation reaction.
[0010] (3) After the reaction is completed, the mixture is centrifuged and washed and then dried overnight, and the obtained material is the phytic acid functionalized fly ash floating bead adsorption material.
[0011] (4) The dried phytic acid functionalized fly ash beads are used for organic dyes.
[0012] Furthermore, the mesh size of the fly ash floating beads in step (1) is 20-200 meshes.
[0013] Furthermore, the concentration of the phytic acid solution in step (2) is 50%-70%.
[0014] Furthermore, in step (2), the mass ratio of fly ash floating beads to phytic acid is 1:5-10.
[0015] Furthermore, the reaction conditions of the polycondensation reaction in step (2) include: a reaction temperature of 100-180° C., a timing start after the polycondensation reaction temperature is reached, and a reaction time of 12-24 hours.
[0016] Furthermore, the centrifugation in step (3) is performed at 12000 r / min for 5 min; the washing is performed twice with ethanol and deionized water; and the drying is performed in a vacuum oven at 70° C. for 5-12 h.
[0017] Furthermore, the phytic acid functionalized fly ash beads in step (4) are used in organic dyes, and the organic dyes mainly include cationic dyes, such as methylene blue dye (MB) and basic magenta green dye (MG).
[0018] Furthermore, the initial concentration of the organic dye in step (4) is 50-4500 mg / L.
[0019] Furthermore, in the step (4), the phytic acid functionalized fly ash floating beads achieve a removal rate of not less than 90% during the treatment of 20 mL of 100 mg / L dye.
[0020] The present invention also provides an organic dye adsorption material prepared by any one of the above preparation methods.
[0021] The phytic acid functionalized fly ash floating bead adsorption material provided by the invention can be applied to waste resource utilization and sewage treatment, and can be particularly applied to the treatment of organic dye wastewater pollution.
[0022] The present invention has the following advantages:
[0023] 1. The phytic acid functionalized fly ash floating bead adsorption material provided by the present invention has low raw material cost, simple process, good adsorption effect on organic dyes in printing and dyeing wastewater, and high social and economic value.
[0024] 2. The raw materials used in the phytic acid functionalized fly ash floating bead adsorption material provided by the present invention are all environmentally friendly substances, and no harmful or toxic substances are used in the preparation process. At the same time, it can realize the resource utilization of industrial waste, which is a green and environmentally friendly method for environmental pollution control.
[0025] 3. The present invention generates less waste discharge when treating organic dye wastewater and is environmentally friendly.
[0026] 4. The present invention provides a composite solution of phytic acid functionalized fly ash floating bead adsorption material, which expands the application of industrial waste in environmental treatment. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 Preparation idea for Example 1
[0028] Figure 2 The scanning electron microscope (SEM) images of the phytic acid functionalized fly ash floating bead adsorption material prepared in Example 1 at different magnifications;
[0029] Figure 3 This is the XRD pattern of the phytic acid functionalized fly ash floating bead adsorption material prepared in Example 1;
[0030] Figure 4 The adsorption effect of the phytic acid functionalized fly ash floating bead adsorption material prepared in Examples 1 and 2 on MB was measured;
[0031] Figure 5 Determination of the adsorption effect of the phytic acid functionalized fly ash floating beads adsorption material of different mesh sizes prepared in Example 1 on MB;
[0032] Figure 6 The adsorption kinetic curve of MB and MG by the phytic acid functionalized fly ash floating bead adsorption material prepared in Example 1;
[0033] Figure 7 This is the adsorption isotherm curve of MB and MG by the phytic acid functionalized fly ash floating bead adsorption material prepared in Example 1. DETAILED DESCRIPTION
[0034] In order to further illustrate the phytic acid functionalized fly ash floating bead adsorption material and its preparation method in the present invention, the intended purpose of the invention is achieved. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0035] Example 1 (50% phytic acid modified 40-100 mesh fly ash floating beads)
[0036] This embodiment provides a method for preparing a phytic acid functionalized fly ash floating bead adsorption material, and the specific steps are as follows:
[0037] The pretreated industrial waste was obtained by selecting fly ash beads with a mesh size of 40-100, screening, washing, and drying in an oven at 60°C. The pretreated industrial waste was mixed with a 50% phytic acid solution at a mass ratio of 1:5, and ultrasonic treatment was performed for 10 minutes to uniformly disperse the fly ash beads in the solution. The polycondensation reaction was carried out in an oven, and the reaction temperature was set to 160°C. The timing was started after the polycondensation reaction temperature was reached, and the reaction time was 24 hours. After the reaction was completed, the mixture was cooled to room temperature and centrifuged at 12000r / min for 5 minutes. After the centrifugation, the supernatant was poured off, and an appropriate amount of anhydrous ethanol and deionized water were added for washing, and then centrifuged again. The action was repeated 3 times, and the obtained mixture was placed in an oven at 70°C for 10 hours. The obtained material was a 50% phytic acid functionalized fly ash bead adsorption material. The composite adsorbent material was characterized, and the adsorption kinetics curve and adsorption thermodynamics curve of the adsorbent were tested.
[0038] Figure 1 This is the preparation idea of phytic acid functionalized fly ash floating bead adsorption material in Example 1.
[0039] Figure 2 The scanning electron microscope images (c, d) of the phytic acid functionalized fly ash floating bead adsorption material prepared in Example 1 at different magnifications and the scanning electron microscope images (a, b) of the original fly ash floating beads at different magnifications show that phytic acid is successfully loaded on the surface of the fly ash floating beads, and the surface of the functionalized floating beads becomes rough from smooth, and the number of pores on the surface of the floating beads increases, thereby improving the adsorption effect of the material, better removing methylene blue dye and alkaline magenta dye in water, and reducing pollution to water bodies.
[0040] Figure 3 The XRD diagram of the fly ash floating bead adsorption material functionalized with phytic acid in Example 1. The crystalline phase of the unmodified fly ash floating beads is mainly quartz and mullite, with high characteristic diffraction peak intensity, sharp peak shape and high crystallinity. The sharp crystalline peak intensity of the fly ash floating beads functionalized with phytic acid is reduced, the non-crystalline phase is reduced but the characteristic peak of the original fly ash floating beads is still retained.
[0041] Example 2 (70% phytic acid modified 40-100 mesh fly ash floating beads)
[0042] This embodiment provides a method for preparing a phytic acid functionalized fly ash floating bead adsorption material, and the specific operation steps are as follows:
[0043] The fly ash beads with a mesh size of 40-100 are selected and sieved, washed, and dried in an oven at 60°C to obtain pretreated industrial waste. The pretreated beads are mixed with a 70% phytic acid solution at a mass ratio of 1:5, and ultrasonically treated for 10 minutes to evenly disperse the fly ash beads in the solution. The polycondensation reaction is carried out in an oven. The reaction temperature is set to 160°C. The timing starts after the polycondensation reaction temperature is reached. The reaction time is 24 hours. After the reaction is completed, the mixture is cooled to room temperature and centrifuged at 12000r / min for 5 minutes. After the centrifugation, the supernatant is poured off, and an appropriate amount of anhydrous ethanol and deionized water are added for washing, and then centrifuged again. The action is repeated 3 times. The obtained material is placed in an oven at 70°C and dried for 10 hours. The obtained material is a 70% phytic acid functionalized fly ash bead adsorption material.
[0044] Example 3 (50% phytic acid modified 20-40 mesh fly ash floating beads)
[0045] This embodiment provides a method for preparing a phytic acid functionalized fly ash floating bead adsorption material, and the specific operation steps are as follows:
[0046] The fly ash beads with a mesh size of 20-40 are selected and sieved, washed, and dried in an oven at 60°C to obtain pretreated industrial waste. The pretreated industrial waste is then mixed with a 50% phytic acid solution at a mass ratio of 1:5, and ultrasonically treated for 10 minutes to evenly disperse the fly ash beads in the solution. The polycondensation reaction is carried out in an oven, and the reaction temperature is set to 160°C. The timing starts after the polycondensation reaction temperature is reached, and the reaction time is 24 hours. After the reaction is completed, the mixture is cooled to room temperature and centrifuged at 12000r / min for 5 minutes. After the centrifugation, the supernatant is poured off, and an appropriate amount of anhydrous ethanol and deionized water are added for washing, and then centrifuged again. The action is repeated 3 times, and the obtained substance is placed in an oven at 70°C for 10 hours. The obtained material is a 50% phytic acid functionalized fly ash bead adsorption material.
[0047] Example 4 (50% phytic acid modified 30-60 mesh fly ash floating beads)
[0048] The fly ash beads with a mesh size of 30-60 are selected and sieved, washed, and dried in an oven at 60°C to obtain pretreated industrial waste. The pretreated industrial waste is then mixed with a 50% phytic acid solution at a mass ratio of 1:5, and ultrasonically treated for 10 minutes to evenly disperse the fly ash beads in the solution. The polycondensation reaction is carried out in an oven, and the reaction temperature is set to 160°C. The timing starts after the polycondensation reaction temperature is reached, and the reaction time is 24 hours. After the reaction is completed, the mixture is cooled to room temperature and centrifuged at 12000r / min for 5 minutes. After the centrifugation, the supernatant is poured off, and an appropriate amount of anhydrous ethanol and deionized water are added for washing, and then centrifuged again. The action is repeated 3 times, and the obtained substance is placed in an oven at 70°C for 10 hours. The obtained material is a 50% phytic acid functionalized fly ash bead adsorption material.
[0049] Example 5 (100-200 mesh fly ash floating beads modified with 50% phytic acid)
[0050] The fly ash beads with a mesh size of 100-200 are selected and sieved, washed, and dried in an oven at 60°C to obtain pretreated industrial waste. The pretreated industrial waste is then mixed with a 50% phytic acid solution at a mass ratio of 1:5, and ultrasonically treated for 10 minutes to evenly disperse the fly ash beads in the solution. The polycondensation reaction is carried out in an oven, and the reaction temperature is set to 160°C. The timing starts after the polycondensation reaction temperature is reached, and the reaction time is 24 hours. After the reaction is completed, the mixture is cooled to room temperature and centrifuged at 12000r / min for 5 minutes. After the centrifugation, the supernatant is poured off, and an appropriate amount of anhydrous ethanol and deionized water are added for washing, and then centrifuged again. The action is repeated 3 times, and the resulting mixture is placed in an oven at 70°C and dried for 10 hours. The resulting material is a 50% phytic acid functionalized fly ash bead adsorption material.
[0051] In the present invention, the application preferably includes the following steps: adding the phytic acid functionalized fly ash floating bead adsorption material into a solution to be tested for adsorption.
[0052] In the present invention, the organic dyes in the test solution are preferably methylene blue dye (MB) and basic magenta green dye (MG).
[0053] In the present invention, the adsorption temperature is preferably 20-40°C and the adsorption time is 10-360 min.
[0054] Determination of the adsorption effect of phytic acid functionalized fly ash beads on MB dye at different concentrations in Examples 1 and 2
[0055] Accurately weigh 25 mg of MB dye using a balance and dissolve it in 250 ml of deionized water to prepare a 100 mg / L MB solution for later use.
[0056] 0.3 g of the phytic acid functionalized fly ash floating bead adsorption material prepared in Example 1 and Example 2 was added to a 50 ml conical flask, and 20 ml of 100 mg / L MB dye of different pH values was added. The conical flask was placed in a water bath constant temperature oscillator, and adsorption was carried out continuously at 30° C. and 200 rpm for 360 min. After the adsorption was completed, the supernatant was taken and the absorbance of the MB solution was measured at a maximum wavelength of 664 nm using a UV-visible spectrophotometer.
[0057] The removal rates of MB by the functionalized adsorption materials of fly ash beads with different concentrations of phytic acid were obtained as follows: Figure 4 As shown in the figure, it was found that when the pH was 10, the removal rates of methylene blue dye by 50% phytic acid functionalized fly ash beads and 70% phytic acid functionalized fly ash beads were 92.33% and 75.32%, respectively. Analysis showed that with the increase of phytic acid concentration, the dispersion of fly ash beads was poor due to the thick 70% phytic acid solution; when the phytic acid concentration was 50%, the fly ash beads were evenly mixed in the phytic acid solution without agglomeration and had good dispersion. The surface of the fly ash beads functionalized with phytic acid had abundant oxygen-containing groups, which adsorbed cationic dyes through electrostatic action, and then completed the adsorption of organic dyes.
[0058] Example 1 Determination of the adsorption effect of 50% phytic acid functionalized fly ash floating beads on MB
[0059] 1. Determination of the adsorption effect of phytic acid functionalized fly ash beads of different mesh sizes on MB
[0060] 0.3 g of phytic acid functionalized fly ash floating beads with different mesh sizes were weighed and placed in a 50 ml conical flask, 20 ml of 100 mg / L MB solution was added, the pH was adjusted to 10, and the mixture was placed on a constant temperature shaker at 30 ° C for 360 min. After the reaction was completed, centrifugation was performed, and the supernatant was taken to measure the absorbance of the MB solution at a maximum wavelength of 664 nm.
[0061] The removal rates of MB by phytic acid functionalized fly ash floating beads with different mesh sizes are as follows: Figure 5 The removal rate of MB by phytic acid functionalized fly ash floating beads of different mesh sizes is above 90%, especially when the mesh size is 40-100 mesh, the removal rate of MB is the highest, reaching 92.33%.
[0062] 2. Kinetic curves of MB and MG adsorption by phytic acid functionalized fly ash beads
[0063] Weigh 0.3 g of 40-100 mesh phytic acid functionalized fly ash floating beads adsorption material into a 50 ml conical flask, add 20 ml of 100 mg / L MB and MG solutions respectively, adjust the pH to 10, place it on a constant temperature shaker at 30 °C for 390 min, take out the conical flask at different time intervals (30, 60, 90, 120, 180, 210, 240, 270, 300, 330, 360, 390 min), and measure the absorbance of MG and MB at wavelengths of 616.6 and 664 nm, respectively, using a UV-visible spectrophotometer. Figure 6 The results showed that the removal rates of MB and MG increased continuously with the progress of time, reaching 92.28% and 97.98% respectively after 360 min, and then remained unchanged to reach equilibrium.
[0064] Example 1 The adsorption results of MB and MG dyes on PA-FAC were fitted by pseudo-first-order kinetics and pseudo-second-order kinetics models. The pseudo-first-order and pseudo-second-order formulas are as follows:
[0065]
[0066] Where q e ,q t are the adsorption amount of dye at adsorption equilibrium and adsorption time t (min), K1 (min -1 ) is the rate constant of the pseudo-first-order model, and K2 (g / (mg·min)) is the kinetic rate constant of the pseudo-second-order kinetic model. Figure 6 The data in Table 1 show that the adsorption of MB and MG by PA-FAC is more consistent with the pseudo-second-order kinetic model, and the correlation coefficient R 2 Greater than 0.99
[0067] Table 1 Related data obtained when fitting using pseudo-first-order kinetics and pseudo-second-order kinetics models
[0068]
[0069]
[0070] 3. Adsorption isotherms of MB and MG on phytic acid functionalized fly ash beads
[0071] The present invention uses the Langmuir isotherm and the Freundlich isotherm to perform data fitting, and the formula is as follows:
[0072]
[0073] Where C0 (mg / L) is the initial concentration of the dye; C e (mg / L) is the concentration of the dye when adsorption equilibrium is reached; qe (mg / g) is the adsorption capacity at adsorption equilibrium; q m (mg / g) is the maximum adsorption capacity when adsorption saturation is reached; K L is the Langmuir adsorption constant (related to the adsorption capacity of the adsorbent); K F [(mg / g)(L / mg)1 / n] is the Freundlich isotherm constant; n is the adsorption intensity.
[0074] Table 2 shows the relevant parameters of the Langmuir model and Freundlich model fitting corresponding to the adsorption of MB and MG by PA-FAC. Figure 7 As shown in Table 2, the correlation coefficient R2 obtained by the Langmuir model is greater than the correlation coefficient R2 obtained by the Freundlich model (0.9947>0.9214), indicating that the adsorption is a single layer adsorption. L , after calculation 0<R L <1, indicating the favorableness of the adsorption process.
[0075] Table 2 Relevant parameters for fitting using Langmuir isotherm and Freundlich isotherm
[0076]
[0077] Comparative Example 1
[0078] The difference from Example 1 is the modified 40-100 mesh fly ash floating beads.
[0079] Comparative Example 2
[0080] The difference from Example 1 is the unmodified 20-40 mesh fly ash floating beads.
[0081] Comparative Example 3
[0082] The difference from Example 1 is the unmodified 30-60 mesh fly ash floating beads.
[0083] Comparative Example 4
[0084] The difference from Example 1 is the unmodified 100-200 mesh fly ash floating beads.
[0085] The performance test results of the products of Examples 1-5 and Comparative Examples of the present invention are as follows:
[0086]
[0087] It can be seen from Examples 1-5 and Comparative Examples 1-4 that the product Examples 1-5 of the present invention have excellent removal rates for MB dye and MG dye, and the removal rates are all above 90%;
[0088] Comparison between Examples 1 and 2 shows that the removal rates of MB and MG adsorbed by 50% phytic acid-modified fly ash floating beads are both above 90%, and the performance of the product is the most significant;
[0089] Comparison between Example 1 and Examples 3-5 shows that, considering the recyclability and ease of collection of the adsorption material, when the mesh size of the fly ash floating beads modified with 50% phytic acid is 40-100 mesh, the adsorption effect on MB and MG is relatively excellent;
[0090] When fly ash beads of different mesh sizes are not modified, the removal rate of the two dyes by the beads tends to be significantly worse. Only the phytic acid functionalized fly ash beads adsorption material obtained by the method of the present invention has significant performance effects, and other methods are not as significant as the effects of the present invention.
[0091] The above is only a preferred embodiment of the embodiment of the present invention, and does not impose any form of limitation on the embodiment of the present invention. Any simple modification, equivalent changes and modifications made to the above embodiment based on the technical essence of the embodiment of the present invention are still within the scope of the technical solution of the embodiment of the present invention.
Claims
1. A method for preparing a phytic acid functionalized fly ash floating bead adsorption material, characterized in that: The steps include: (1) Fly ash beads of different mesh sizes are screened, washed, and dried to obtain pre-treated industrial waste; (2) mixing the pretreated industrial waste with the phytic acid solution in a certain mass ratio, ultrasonically homogenizing the mixture, and placing the mixture in an oven for polycondensation reaction; (3) After the reaction is completed, the mixture is centrifuged and washed and then dried overnight, and the resulting material is the phytic acid functionalized fly ash floating bead adsorption material.
2. The preparation method according to claim 1, characterized in that: The mesh size of the fly ash floating beads in step (1) is 20-200 meshes.
3. The preparation method according to claim 1, characterized in that: The concentration of the phytic acid solution in step (2) is 50%-70%.
4. The preparation method according to claim 1, characterized in that: In the step (2), the mass ratio of fly ash beads to phytic acid is 1:5-10.
5. The preparation method according to claim 1, characterized in that: The reaction conditions of the polycondensation reaction in step (2) include: a reaction temperature of 100-180° C., a timing start after the polycondensation reaction temperature is reached, and a reaction time of 12-24 hours.
6. The preparation method according to claim 1, characterized in that: The centrifugation in step (3) is performed at 12000 r / min for 5 min; the washing is performed twice with ethanol and deionized water; the drying is performed under vacuum at 70° C. for 5-12 h.
7. A plant acid functionalized fly ash floating bead adsorption material, characterized in that: The preparation method is described in claims 1 to 6.
8. Use of the phytic acid functionalized fly ash floating bead adsorption material as claimed in claim 7 in waste resource utilization and pollution control.
9. The use according to claim 8, characterized in that: The pollution includes organic dye wastewater pollution.