Sediment-based photo-thermal conversion material, preparation method and application thereof
Patent Information
- Application Number
- CN202311486469.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-11-09
- Publication Date
- 2026-09-29
- Estimated Expiration
- 2043-11-09
AI Technical Summary
[0003]现有技术中，常见的光热转化材料有如吸光氧化物钛酸锶和铈氧化物等吸光氧化物，以及铜铟镓硒(CIGS)等光热半导体，但是这些材料制备成本较高，不利于推广进行大规模生产使用
[0023]本发明以泥沙为基体材料，泥沙是一种广泛存在于自然环境中的物质，原料易得且使用泥沙作为光热转化材料成本低，可以避免对其他资源的过度依赖；与其他做为基体的昂贵且复杂的材料相比而言，具有极高的经济利用价值。
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Abstract
Description
Technical Field
[0001] This invention relates to the field of photothermal conversion materials technology, and in particular to a mud-and-sand-based photothermal conversion material, its preparation method, and its application. Background Technology
[0002] Photothermal conversion materials are substances that can convert sunlight or other light sources into heat energy. These materials have a high light absorption rate, enabling them to effectively absorb light energy and convert it into heat energy. Furthermore, photothermal conversion materials have broad application prospects in technologies such as solar energy utilization, thermoelectric energy, and solar thermal power generation because they can effectively utilize renewable energy sources, reduce energy consumption and environmental pollution.
[0003] In existing technologies, common photothermal conversion materials include light-absorbing oxides such as strontium titanate and cerium oxide, as well as photothermal semiconductors such as copper indium gallium selenide (CIGS). However, these materials have high preparation costs, which is not conducive to their large-scale production and use. Therefore, it is very important to provide a new type of photothermal conversion material with low preparation cost and simple preparation process.
[0004] Therefore, this invention provides a silt-based photothermal conversion material, its preparation method, and its application. Summary of the Invention
[0005] To address the shortcomings of the existing technology, this invention provides a silt-based photothermal conversion material, its preparation method, and its application. This invention considers that silt itself possesses photothermal conversion capabilities, but these capabilities are limited. Furthermore, when a single TA-Fe(III) complex is used as a photothermal conversion material, the TA-Fe(III) complex is dispersed and difficult to concentrate and recover. Therefore, this invention attempts to composite the TA-Fe(III) complex with silt to improve the conversion efficiency of the silt itself by loading TA-Fe(III) onto the silt surface. Simultaneously, the silt has sufficient active sites and pores to provide enough adsorption sites for TA-(III), enabling it to aggregate rather than disperse, thus avoiding loss due to difficulty in collection.
[0006] The present invention provides a silt-based photothermal conversion material, its preparation method, and its application, which are achieved through the following technical solutions:
[0007] The first objective of this invention is to provide a method for preparing a mud-based photothermal conversion material, comprising the following steps:
[0008] The mud and sand are soaked in an alkaline solution for impregnation, washed until the pH is neutral, and then dried to obtain clean mud and sand.
[0009] Tannic acid was uniformly dispersed in an aqueous solvent to obtain a modified solution; subsequently, the clean sludge was placed in the modified solution and subjected to a first stirring treatment to obtain a mixed solution.
[0010] Add Fe to the mixed solution 3+ The source is subjected to a second stirring treatment, followed by solid-liquid separation, washing, and drying to obtain the mud-sand-based photothermal conversion material.
[0011] Preferably, the alkaline solution is a sodium hydroxide solution or a potassium hydroxide solution;
[0012] The concentration of the alkaline solution is 1–2 mol / L.
[0013] Preferably, the ratio of the mud and sand to the alkaline solution is 100g:400-600mL.
[0014] Preferably, the impregnation treatment is carried out under stirring, and the stirring temperature is room temperature, the stirring rate is 200-400 r / min, and the stirring time is 2-6 h.
[0015] Preferably, the ratio of tannic acid to aqueous solvent is 0.27–13.6 g: 100 mL.
[0016] Preferably, the ratio of the clean sludge to the modified liquid is 10g:80-120mL.
[0017] Preferably, the Fe 3+ The source is any one of ferric chloride, ferric sulfate, and ferric nitrate;
[0018] And the Fe 3+ The ratio of the source to the tannic acid added to the mixed solution is 1–50 mmol: 0.27–13.6 g.
[0019] Preferably, the stirring temperature for the first stirring treatment is room temperature, the stirring rate is 200-400 r / min, and the stirring time is 1-3 h.
[0020] Preferably, the stirring temperature for the second stirring treatment is room temperature, the stirring rate is 200-400 r / min, and the stirring time is 1-3 h.
[0021] The second objective of this invention is to provide a mud-based photothermal conversion material prepared by the above-described preparation method.
[0022] Compared with the prior art, the present invention has the following advantages:
[0023] This invention uses silt as the matrix material. Silt is a substance that is widely present in the natural environment. The raw material is readily available and the cost of using silt as a photothermal conversion material is low, which can avoid excessive dependence on other resources. Compared with other expensive and complex materials used as the matrix, it has extremely high economic value.
[0024] This invention modifies silt by soaking it in an alkaline solution, and then selects natural polyphenols tannins (TA) and Fe... 3+ The source, acting as both an organic ligand and an inorganic crosslinking agent, combines natural polyphenolic tannins (TA) and Fe at ambient temperature. 3+ Thin film deposition occurs when the source mixes in water.
[0025] This invention first loads TA onto the surface of sediment through adsorption, and then introduces Fe... 3+ Source, to be obtained through Fe 3+ The TA source and the surface of the silt form a cross-linked film of TA-Fe(III) complex in situ on the surface of the silt through the complexation of coordination bonds. The formed TA-Fe(III) has sufficient functional groups such as carboxyl and hydroxyl groups, which can better interact with the clean silt through covalent and hydrogen bonds, thereby improving the bonding force between the TA-Fe(III) cross-linked film and the clean silt, and obtaining a stable silt-based photothermal conversion material.
[0026] Furthermore, in the silt-based photothermal conversion material obtained by this invention, due to the initial loading of TA, Fe is introduced... 3+ Composite, and by controlling the interaction between TA and Fe 3 of + The optimal concentration ratio allows for a TA-Fe(III) cross-linked film thickness of 8–12 nm to be formed on the surface of the sediment. By altering the pore structure and surface functional groups of the sediment, the absorbance and hydrophilicity of the surface are increased, ensuring that the formed cross-linked film can improve the photothermal conversion efficiency of the sediment-based photothermal conversion material. Furthermore, this invention achieves a synergistic effect between sediment and TA-Fe(III) by forming TA-Fe(III) in situ on the sediment surface. Both can absorb light energy and convert it into heat energy; the combined effect enhances the photothermal conversion efficiency.
[0027] In summary, sediment and TA-Fe(III) can form composite materials through interactions such as adsorption, covalent bonding, hydrogen bonding, and chemical coordination. This composite material can combine the photothermal conversion properties of sediment and TA-Fe(III), enabling the application of photothermal conversion materials. Detailed Implementation
[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below.
[0029] This invention provides a silt-based photothermal conversion material, and its preparation method is as follows:
[0030] The mud and sand are soaked in an alkaline solution for impregnation, washed until the pH is neutral, and then dried to obtain clean mud and sand.
[0031] Tannic acid was uniformly dispersed in an aqueous solvent to obtain a modified solution; subsequently, the clean sludge was placed in the modified solution and subjected to a first stirring treatment to obtain a mixed solution.
[0032] Add Fe to the mixed solution 3+ The source is subjected to a second stirring treatment, followed by solid-liquid separation, washing, and drying to obtain the mud-sand-based photothermal conversion material.
[0033] It should be noted that the matrix material used in this invention is silt, a substance widely found in the natural environment. The raw material is readily available, and using silt as a photothermal conversion material is low-cost, avoiding excessive reliance on other resources. Compared to other expensive and complex materials used as matrices, it has extremely high economic value. Furthermore, before modifying the silt, this invention first immerses it in an alkaline solution to clean away impurities attached to the silt through alkaline soaking.
[0034] To ensure that the alkaline solution can fully remove impurities from the silt, in a preferred embodiment of the present invention, a sodium hydroxide solution or potassium hydroxide solution with a concentration of 1-2 mol / L is used as the alkaline solution, and the ratio of silt to the alkaline solution is 100g:400-600mL. The impregnation treatment is carried out under stirring, with the stirring temperature at room temperature, the stirring rate at 200-400 r / min, and the stirring time at 2-6 h.
[0035] To avoid the alkaline solution affecting the subsequent modification treatment, the product obtained from the impregnation treatment is also washed using deionized water and ethanol as detergents, alternately until the pH is neutral, to remove residual alkaline solution from the clean mud and sand surface, and then dried to remove residual detergent. In a preferred embodiment of the invention, the drying temperature is 70–90°C, and the drying time is 12–32 hours.
[0036] This invention uses tannic acid (TA) as a modifier, which is uniformly dispersed in an aqueous solvent. The aqueous solution of tannic acid is used as the modifying liquid, and then the clean silt treated above is added. Since the surface of the clean silt has sufficient hydroxyl groups and active sites, it is conducive to the adsorption and loading of tannic acid. Then, through stirring, the tannic acid in the modifying liquid is fully contacted. Tannic acid has extremely strong surface affinity, so it can be fully adsorbed and loaded on the surface of the clean silt particles to form a precursor of silt-based photothermal conversion material.
[0037] To ensure that tannic acid can be uniformly dispersed in the aqueous solvent, in a preferred embodiment of the present invention, ultrasonic dispersion is used, and the ratio of tannic acid to aqueous solvent is 0.27-13.6 g: 100 mL, the ultrasonic frequency is 40-55 kHz, and the ultrasonic time is 15-45 min.
[0038] To ensure that tannic acid can be uniformly adsorbed and loaded onto the clean mud and sand surface, in a preferred embodiment of the present invention, the stirring process is as follows: the stirring temperature is room temperature, the stirring rate is 200-400 r / min, and the stirring time is 1-3 h.
[0039] This invention involves adding Fe to a solution of clean mud and sand with tannic acid loaded on its surface, i.e., to the aforementioned mixed solution. 3+ The source is mixed evenly and stirred to allow Fe to be stirred. 3+ Fe in the source 3+ It comes into full contact with the tannic acid loaded on the surface of clean mud and sand, and each Fe 3+ It can coordinate with the three hydroxyl groups on tannic acid; at the same time, the three toluenepropyl groups in tannic acid can react with Fe. 3+ The reaction forms a stable octahedral complex, which in turn allows Fe to... 3+ After reacting with tannic acid, a cross-linked film of TA-Fe(III) complex is formed on the surface of clean mud and sand. The formed TA-Fe(III) has sufficient functional groups such as carboxyl and hydroxyl groups, which can better interact with clean mud and sand through covalent and hydrogen bonds, thereby improving the bonding force between the TA-Fe(III) cross-linked film and clean mud and sand, and obtaining a stable mud and sand-based photothermal conversion material.
[0040] To ensure Fe 3+ A cross-linked film that can form with tannic acid on the surface of clean silt can improve the photothermal conversion efficiency of silt-based photothermal conversion materials. This avoids situations where the cross-linked film is too thin, failing to effectively improve the photothermal conversion efficiency of the silt matrix; conversely, if the cross-linked film is too thick, the bonding force between the film and the matrix weakens, thus hindering the synergistic effect between the silt and the TA-Fe(III) cross-linked film and failing to effectively improve the photothermal conversion efficiency of the silt matrix. In a preferred embodiment of this invention, the ratio of tannic acid to the aqueous solvent in the modified solution is controlled to be 0.27–13.6 g:100 mL, and the ratio of clean silt to the modified solution is controlled to be 10 g:80–120 mL, and the Fe... 3+ The ratio of the amount of tannic acid added to the source and the mixed solution is 1–50 mmol: 0.27–13.6 g, thereby controlling the thickness of the formed cross-linked film to be 8–12 nm, thus ensuring that the formed cross-linked film can improve the photothermal conversion efficiency of the mud-based photothermal conversion material.
[0041] To ensure Fe 3+ It can fully react with the tannic acid on the surface of clean mud and sand to form a cross-linked film. In a preferred embodiment of the present invention, the stirring process is as follows: the stirring temperature is room temperature, the stirring rate is 200-400 r / min, and the stirring time is 1-3 h.
[0042] It should be noted that the present invention is based on composite Fe 3+ When dealing with clean sludge with TA surface loading, it is not necessary to separate the TA-loaded clean sludge from the prepared mixed solution; Fe can be added directly to it. 3+ The reaction can proceed simply by mixing the source material thoroughly, which simplifies the operation and shortens the processing time. Furthermore, Fe... 3+ The reaction process with TA on the surface of clean sediment is extremely rapid, occurring directly at the interface where clean sediment and TA combine, thus forming a TA-Fe(III) complex on the surface of the clean sediment. The assembly process is simple and quick, saving both economic and time costs. Sediment itself can absorb a significant amount of light and convert it into heat.
[0043] Sediment possesses excellent thermal capacity, enabling it to store and release heat energy over extended periods. Furthermore, TA-Fe(III), a black complex, absorbs light energy and undergoes intramolecular dd transitions, converting light energy into heat energy. It exhibits superior photothermal conversion properties, possessing not only excellent light absorption for ample illumination but also excellent thermal conductivity. When exposed to light, TA-Fe(III) absorbs light energy and converts it into heat. Combining sediment with TA-Fe(III) achieves a synergistic effect, as both can absorb light energy and convert it into heat energy; the combined effect enhances the efficiency of photothermal conversion.
[0044] It should also be noted that in the following embodiments of the present invention, Yellow River silt is used as the silt raw material. The silt is washed with distilled water and then dried for use in the following embodiments.
[0045] Example 1
[0046] This embodiment provides a silt-based photothermal conversion material, and its preparation method is as follows:
[0047] Step 1, Prepare clean sludge
[0048] 1) Dissolve sodium hydroxide in deionized water to prepare a sodium hydroxide solution with a concentration of 1.5 mol / L as an alkaline solution;
[0049] 2) Add the mud and sand to the prepared alkaline solution at a ratio of 100g mud and sand to 500mL alkaline solution, stir at a stirring rate of 300r / min for 4h, let it stand and separate into layers, remove the upper clear liquid, and obtain the solid component.
[0050] 3) The solid components obtained above were washed alternately with deionized water and ethanol as detergents until the pH of the washing solution was neutral. Then, they were dried in an oven at 80°C for 24 hours to obtain clean mud and sand.
[0051] Step 2, Compound Tannic Acid and Cleaned Sludge:
[0052] 1) Weigh 0.2703g TA into a 250mL beaker, then add 100mL of distilled water, and then place it in an ultrasonic cleaner. Under ultrasonic conditions at a frequency of 53kHz for 30min, the TA will be fully dissolved in the distilled water to obtain a TA solution.
[0053] 2) Take 10g of the clean sludge obtained in step 1 above and add it to the TA solution prepared in step 1) above. Stir at 300r / min for 2h at room temperature so that TA and clean sludge can fully contact and combine during the stirring process, thereby forming a sludge-based photothermal conversion material precursor in the solution, and obtaining a mixed solution of clean sludge loaded with TA on the surface.
[0054] Step 3, composite Fe 3+ Clean sludge with TA surface loading:
[0055] 1) Using FeCl3·6H2O as Fe 3+ The source was determined, and 0.2703 g of FeCl3·6H2O was dissolved in 100 mL of distilled water by ultrasonication to obtain FeCl3 with a concentration of 0.01 mol / L. 3+ Source solution;
[0056] 2) The Fe3O4 solution prepared above with a concentration of 0.01 mol / L was used. 3+ The source solution was added to the mixed solution prepared in step 2, and stirred at 300 r / min for 2 h at room temperature to achieve Fe. 3+ The solid component is obtained after solid-liquid separation following the combination of the composite with clean sludge and sand with TA loaded on the surface.
[0057] 3) After washing the solid components obtained above until the solution is transparent, dry them in an oven at 80°C for 24 hours to obtain the mud-sand-based photothermal conversion material of this embodiment.
[0058] Example 2
[0059] This embodiment provides a silt-based photothermal conversion material, and its preparation method is as follows:
[0060] Step 1, Prepare clean sludge
[0061] 1) Dissolve sodium hydroxide in deionized water to prepare a sodium hydroxide solution with a concentration of 1.5 mol / L as an alkaline solution;
[0062] 2) Add silt with a particle size of 100-200 mesh to the prepared alkaline solution at a ratio of 100g silt to 500mL alkaline solution. Stir at a stirring rate of 300r / min for 4 hours. After standing and separating into layers, remove the upper clear liquid to obtain the solid component.
[0063] 3) The solid components obtained above were washed alternately with deionized water and ethanol as detergents until the pH of the washing solution was neutral. Then, they were dried in an oven at 80°C for 24 hours to obtain clean mud and sand.
[0064] Step 2, Compound Tannic Acid and Cleaned Sludge:
[0065] 1) Weigh 1.3515g TA into a 250mL beaker, then add 100mL of distilled water, and then place it in an ultrasonic cleaner. Under ultrasonic conditions at a frequency of 53kHz for 30min, the TA will be fully dissolved in the distilled water to obtain a TA solution.
[0066] 2) Take 10g of the clean sludge obtained in step 1 above and add it to the TA solution prepared in step 1) above. Stir at 300r / min for 2h at room temperature so that TA and clean sludge can fully contact and combine during the stirring process, thereby forming a sludge-based photothermal conversion material precursor in the solution, and obtaining a mixed solution of clean sludge loaded with TA on the surface.
[0067] Step 3, composite Fe 3+ Clean sludge with TA surface loading:
[0068] 1) Using FeCl3·6H2O as Fe 3+ The source was determined, and 1.3515 g of FeCl3·6H2O was dissolved in 100 mL of distilled water by ultrasonication to obtain FeCl3 with a concentration of 0.05 mol / L. 3+ Source solution;
[0069] 2) The Fe3O4 solution prepared above has a concentration of 0.05 mol / L. 3+ The source solution was added to the mixed solution prepared in step 2, and stirred at 300 r / min for 2 h at room temperature to achieve Fe. 3+ The solid component is obtained after solid-liquid separation following the combination of the composite with clean sludge and sand with TA loaded on the surface.
[0070] 3) After washing the solid components obtained above until the solution is transparent, dry them in an oven at 80°C for 24 hours to obtain the mud-sand-based photothermal conversion material of this embodiment.
[0071] Example 3
[0072] This embodiment provides a silt-based photothermal conversion material, and its preparation method is as follows:
[0073] Step 1, Prepare clean sludge
[0074] 1) Dissolve sodium hydroxide in deionized water to prepare a sodium hydroxide solution with a concentration of 1.5 mol / L as an alkaline solution;
[0075] 2) Add the mud and sand to the prepared alkaline solution at a ratio of 100g mud and sand to 500mL alkaline solution, stir at a stirring rate of 300r / min for 4h, let it stand and separate into layers, remove the upper clear liquid, and obtain the solid component.
[0076] 3) The solid components obtained above were washed alternately with deionized water and ethanol as detergents until the pH of the washing solution was neutral. Then, they were dried in an oven at 80°C for 24 hours to obtain clean mud and sand.
[0077] Step 2, Compound Tannic Acid and Cleaned Sludge:
[0078] 1) Weigh 2.7029g and place it in a 250mL beaker, then add 100mL of distilled water, and then place it in an ultrasonic cleaner. Under ultrasonic conditions at a frequency of 53kHz for 30min, the TA will be fully dissolved in the distilled water to obtain a TA solution.
[0079] 2) Take 10g of the clean sludge obtained in step 1 above and add it to the TA solution prepared in step 1) above. Stir at 300r / min for 2h at room temperature so that TA and clean sludge can fully contact and combine during the stirring process, thereby forming a sludge-based photothermal conversion material precursor in the solution, and obtaining a mixed solution of clean sludge loaded with TA on the surface.
[0080] Step 3, composite Fe 3+ Clean sludge with TA surface loading:
[0081] 1) Using FeCl3·6H2O as Fe 3+ The source was determined, and 2.7029 g of FeCl3·6H2O was dissolved in 100 mL of distilled water by ultrasonication to obtain FeCl3 with a concentration of 0.1 mol / L. 3+ Source solution;
[0082] 2) The Fe3O4 solution prepared above with a concentration of 0.1 mol / L was used.3+ The source solution was added to the mixed solution prepared in step 2, and stirred at 300 r / min for 2 h at room temperature to achieve Fe. 3+ The solid component is obtained after solid-liquid separation following the combination of the composite with clean sludge and sand with TA loaded on the surface.
[0083] 3) After washing the solid components obtained above until the solution is transparent, dry them in an oven at 80°C for 24 hours to obtain the mud-sand-based photothermal conversion material of this embodiment.
[0084] Example 4
[0085] This embodiment provides a silt-based photothermal conversion material, and its preparation method is as follows:
[0086] Step 1, Prepare clean sludge
[0087] 1) Dissolve sodium hydroxide in deionized water to prepare a sodium hydroxide solution with a concentration of 1.5 mol / L as an alkaline solution;
[0088] 2) Add the mud and sand to the prepared alkaline solution at a ratio of 100g mud and sand to 500mL alkaline solution, stir at a stirring rate of 300r / min for 4h, let it stand and separate into layers, remove the upper clear liquid, and obtain the solid component.
[0089] 3) The solid components obtained above were washed alternately with deionized water and ethanol as detergents until the pH of the washing solution was neutral. Then, they were dried in an oven at 80°C for 24 hours to obtain clean mud and sand.
[0090] Step 2, Compound Tannic Acid and Cleaned Sludge:
[0091] 1) Weigh 13.5125g of TA into a 250mL beaker, then add 100mL of distilled water, and then place it in an ultrasonic cleaner. Under ultrasonic conditions at a frequency of 53kHz for 30min, the TA will be fully dissolved in the distilled water to obtain a TA solution.
[0092] 2) Take 10g of the clean sludge obtained in step 1 above and add it to the TA solution prepared in step 1) above. Stir at 300r / min for 2h at room temperature so that TA and clean sludge can fully contact and combine during the stirring process, thereby forming a sludge-based photothermal conversion material precursor in the solution, and obtaining a mixed solution of clean sludge loaded with TA on the surface.
[0093] Step 3, composite Fe 3+ Clean sludge with TA surface loading:
[0094] 1) Using FeCl3·6H2O as Fe3+ The source was determined, and 13.5125 g of FeCl3·6H2O was weighed and dissolved in 100 mL of distilled water by ultrasonication to obtain FeCl3 with a concentration of 0.5 mol / L. 3+ Source solution;
[0095] 2) The Fe3O4 solution prepared above with a concentration of 0.5 mol / L was used. 3+ The source solution was added to the mixed solution prepared in step 2, and stirred at 300 r / min for 2 h at room temperature to achieve Fe. 3+ The solid component is obtained after solid-liquid separation following the combination of the composite with clean sludge and sand with TA loaded on the surface.
[0096] 3) After washing the solid components obtained above until the solution is transparent, dry them in an oven at 80°C for 24 hours to obtain the mud-sand-based photothermal conversion material of this embodiment.
[0097] Comparative Example 1
[0098] The only difference between this comparative example and Example 1 is that:
[0099] This comparative example does not modify the sediment; that is, the photothermal conversion material provided in this comparative example is pure sediment.
[0100] Experimental Section
[0101] This invention takes the materials prepared in Examples 1-4 and Comparative Example 1 as examples, respectively, and prepares each material into a mud and sand loading cage. The evaporation performance of the mud and sand loading cages corresponding to each example is tested. The photothermal conversion performance of the mud and sand based photothermal conversion materials of Examples 1-4 and Comparative Example 1 is explained by measuring their water evaporation rate. The test results are shown in Tables 1-5.
[0102] It should be noted that the above-mentioned mud and sand loading cages of the present invention are all obtained through the following steps:
[0103] 1) Three loading cages of the same height are designed for loading mud and sand: the diameter of each of the three loading cages is 2.5cm and the height is 1cm. In addition, the three loading cages of this invention have low thermal conductivity, which can be used for heat insulation and reduce heat loss.
[0104] 2) Based on the dimensions of the three loading cages designed above, establish corresponding 3D models and use polyethylene material to 3D print the three loading cages.
[0105] 3) Lay filter cloth at the bottom of the three printed loading cages, then suspend them above the tops of three 25 mL beakers containing 20 mL of deionized water, and cover the cages with the mud-sand nano-silver composite material prepared in this invention to fix the sand and isolate the heat of the sand from the water, so as to store the heat inside the sand.
[0106] Water distillation performance test:
[0107] With a light intensity of 1kW / m 2 A xenon lamp was used to simulate sunlight. The prepared sediment cages were placed under the xenon lamp, and the lamp diameter was adjusted to match the diameter of the evaporation device. While the samples were irradiated by simulated sunlight, the mass change of the water was monitored in real time using an electronic balance. Simultaneously, the surface temperature change of the samples was monitored in real time. Each sample was tested for one hour, with data recorded every five minutes, and parallel tests were conducted two or three times. The evaporation performance of Yellow River sediment was analyzed, and its evaporation patterns were studied.
[0108] Table 1 Test results of Example 1
[0109]
[0110] Table 2 Test results of Example 2
[0111]
[0112]
[0113] Table 3 Test results of Example 3
[0114]
[0115] Table 4 Test Results of Example 4
[0116]
[0117]
[0118] Table 5 shows the test results of Comparative Example 1.
[0119] 0 0 0 0 0 0 5 0.0143 0.0184 0.0164 0.002899138 0.516397326 10 0.0333 0.0420 0.0377 0.006151829 0.594567563 15 0.0574 0.0718 0.0646 0.010182338 0.680107385 20 0.0836 0.1028 0.0932 0.01357645 0.735905669 25 0.1129 0.1340 0.1235 0.014919953 0.779807338 30 0.1441 0.1668 0.1555 0.016051324 0.818287098 35 0.1773 0.2003 0.1888 0.016263456 0.851863828 40 0.2117 0.2348 0.2233 0.016334167 0.881389167 45 0.2465 0.2700 0.2583 0.016617009 0.849640733 50 0.2826 0.3054 0.2940 0.016122035 0.928567669 55 0.3184 0.3407 0.3296 0.015768481 0.946225959 60 0.3550 0.3775 0.3663 0.015909903 0.963967995
[0120] Table 1 shows the test results for Example 1, Table 2 shows the test results for Example 2, Table 3 shows the test results for Example 3, Table 4 shows the test results for Example 4, and Table 5 shows the test results for Comparative Example 1. From the test results in Tables 1-5, it can be seen that as the loading of tannic acid on the surface of the sediment increases, its surface reacts with Fe... 3+ The loading of TA-Fe(III) also increases, and the light absorption performance of the formed mud-based photothermal conversion material is enhanced accordingly.
[0121] Surface modification with Fe(III) and TA using silt as a matrix increases the light absorption of the surface by changing the pore structure and surface functional groups of the silt, resulting in high photothermal conversion efficiency.
[0122] This invention uses silt as a matrix, a substance widely found in the natural environment. Using silt as a photothermal conversion material is low-cost, avoids excessive reliance on other resources, and converts silt into heat. Simultaneously, silt possesses excellent thermal capacity, allowing for long-term storage and release of heat energy. Furthermore, this invention modifies the silt matrix with Fe(III) and TA, utilizing the excellent adsorption properties of Fe(III)-TA on the silt to increase its surface absorbance, resulting in high photothermal conversion efficiency. As the amounts of TA and Fe(III) increase simultaneously, the water distillation efficiency of the TA-Fe(III) and silt composite photothermal conversion material also improves. The silt loaded with Fe-TA exhibits better photothermal conversion properties than pure silt.
[0123] Obviously, the above embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.
Claims
1. A method for preparing a mud-based photothermal conversion material, characterized in that, Includes the following steps: The mud and sand are soaked in an alkaline solution for impregnation, washed until the pH is neutral, and then dried to obtain clean mud and sand. Tannic acid was uniformly dispersed in an aqueous solvent to obtain a modified solution; Subsequently, the clean sludge was placed in the modified liquid and subjected to a first stirring treatment to obtain a mixed solution; Add Fe to the mixed solution 3+ The source is subjected to a second stirring treatment, followed by solid-liquid separation, washing, and drying to obtain the mud-sand-based photothermal conversion material. The alkaline solution is a sodium hydroxide solution or a potassium hydroxide solution; The concentration of the alkaline solution is 1~2 mol / L; The ratio of the mud and sand to the alkaline solution is 100g:400~600mL; The impregnation treatment is carried out under stirring, with the stirring temperature at room temperature, the stirring rate at 200~400 r / min, and the stirring time at 2~6 h. The ratio of tannic acid to aqueous solvent is 0.27~13.6g:100mL; The ratio of the clean sludge to the modified liquid is 10g:80~120mL; The Fe 3+ The source is any one of ferric chloride, ferric sulfate, and ferric nitrate; And the Fe 3+ The ratio of the source to the tannic acid added to the mixed solution is 1~50 mmol: 0.27~13.6 g; The stirring temperature for the first stirring treatment was room temperature, the stirring rate was 200~400 r / min, and the stirring time was 1~3 h. The second stirring treatment was carried out at room temperature, with a stirring rate of 200-400 r / min and a stirring time of 1-3 h.
2. A mud-based photothermal conversion material prepared by the preparation method of claim 1.