A cellulose-based fabric photothermal material, its preparation method and application
By loading polyphenol metal complexes and silver nanoparticles onto cellulose fiber fabrics and combining them with a thermal chimney structure, the problem of balancing photothermal conversion performance and antibacterial properties in cellulose-based evaporators is solved, achieving efficient photothermal conversion and stable water evaporation, making it suitable for large-scale applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- DONGHUA UNIV
- Filing Date
- 2025-01-16
- Publication Date
- 2026-06-30
AI Technical Summary
In the existing technology, cellulose-based evaporators have difficulty in achieving both photothermal conversion performance and antibacterial properties, and the high cost of traditional photothermal materials limits their large-scale application.
Using cellulose fiber fabric as a substrate, polyphenol metal coordination complexes and silver nanoparticles are loaded onto it. Cellulose-based fabric photothermal materials are prepared by simple soaking and coordination reduction methods. Combined with a hot chimney structure and evaporation system, the evaporation efficiency and antibacterial properties are improved.
It achieves high-efficiency photothermal conversion performance, with a solar-to-water vapor conversion efficiency of 95.2%. The material has good stability and significant antibacterial properties, making it suitable for large-scale applications.
Smart Images
Figure CN119754026B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of wastewater treatment technology, specifically relating to a cellulose-based fabric photothermal material, its preparation method, and its application. Background Technology
[0002] With rapid industrial development, the large quantities of concentrated brine generated pose challenges to water treatment. High concentrations of brine increase the difficulty and cost of water treatment, negatively impacting the environment and ecosystems. Furthermore, concentrated brine may contain valuable resources; failure to effectively recover and utilize these resources leads to waste. To address these challenges, low-cost concentration and volume reduction methods have become urgently needed. Currently, membrane separation, thermal evaporation, and ion exchange technologies are widely used for treating concentrated brine; however, these technologies are characterized by high energy consumption, limiting their development and application and imposing significant treatment costs on enterprises. Photothermal interfacial evaporation technology utilizes solar energy to drive evaporation, offering advantages such as low energy consumption and low carbon footprint, making it a promising technology for concentrated brine concentration and volume reduction.
[0003] Solar evaporation systems can be categorized into three types: bottom-heated evaporation systems, bulk-heated evaporation systems, and interfacial-heated evaporation systems. Bottom-heated evaporation systems suffer significant solar energy loss, with the overall solar energy utilization rate of the entire solar-driven evaporation system being only 30-45%. Bulk-heated evaporation systems reduce solar energy loss to some extent, but the heating process of nanoparticles inevitably leads to heat loss to non-evaporation areas. Furthermore, carbon-based and metal-based nanoparticles have drawbacks such as difficulty in recycling, high cost, and potential secondary pollution of water bodies, hindering their large-scale application. Interfacial evaporation systems significantly reduce solar energy loss, substantially increasing the temperature of interfacial evaporation and effectively minimizing heat loss to the water body, allowing for rapid evaporation of interfacial water and thus significantly improving solar energy utilization. Therefore, solar interfacial evaporation concentration is currently one of the most promising methods for concentrating saline water and desalination.
[0004] In the design of high-efficiency interface solar steam generators, the selection of photothermal materials is crucial, and the choice of substrate for supporting these materials is particularly important. Traditional synthetic polymers, metal substrates, and semiconductors have high solar-to-thermal energy conversion efficiencies, but their high cost limits their large-scale application.
[0005] Cellulose is widely used as a photothermal carrier due to its good hydrophilicity, high mechanical strength, good flexibility, and low cost. However, in research involving cellulose-based evaporators, high photothermal conversion performance and antibacterial properties cannot be simultaneously achieved, and the performance needs further improvement. Summary of the Invention
[0006] In view of this, the purpose of the present invention is to provide a cellulose-based fabric photothermal material, its preparation method and application, wherein the cellulose-based fabric photothermal material has good stability, excellent photothermal performance and antibacterial properties.
[0007] To achieve the above objectives, the present invention provides the following technical solution:
[0008] This invention provides a cellulose-based fabric photothermal material, comprising: cellulose fiber fabric, a polyphenol metal coordination complex and silver nanoparticles loaded on the surface and pores of the cellulose fiber fabric;
[0009] The polyphenol metal complexes include polyphenol copper complexes, polyphenol trivalent iron complexes, and polyphenol silver complexes.
[0010] Preferably, the cellulose-based fabric photothermal material contains 1-5% by mass of copper polyphenol complex, 1-5% by mass of ferric polyphenol complex, 1-5% by mass of silver polyphenol complex, and 2-5% by mass of silver nanoparticles.
[0011] Preferably, the cellulose fiber fabric includes one or more of cotton cellulose fiber fabric, hemp cellulose fiber fabric, and wood cellulose fiber fabric.
[0012] The present invention also provides a method for preparing the cellulose-based fabric photothermal material described in the above technical solution, comprising the following steps:
[0013] Cellulose fiber fabric is sequentially immersed in alkaline copper salt solution, polyphenol solution, soluble iron salt solution and soluble silver salt solution, and then washed and dried to obtain cellulose-based fabric photothermal material.
[0014] Preferably, the alkaline copper salt solution is a mixed solution of copper salt and sodium hydroxide; the molar ratio of copper salt to sodium hydroxide is 1:1 to 400.
[0015] Preferably, the copper salt includes one or more of copper chloride, copper nitrate, and copper sulfate.
[0016] Preferably, the polyphenols in the polyphenol solution include one or more of tannic acid, phenol-ketone polyphenols, and phenylpropane polyphenols; the concentration of the polyphenols in the polyphenol solution is 2~4 g / L.
[0017] Preferably, the soluble iron salt in the soluble iron salt solution includes one or more of ferric chloride, ferric sulfate, and ferric nitrate; the concentration of the soluble iron salt in the soluble iron salt solution is 0.5~3g / L.
[0018] The present invention also provides the application of the cellulose-based fabric photothermal material described in the above technical solution or the cellulose-based fabric photothermal material prepared by the preparation method described in the above technical solution in the treatment of saline wastewater.
[0019] The present invention also provides a thermal management enhanced interface concentration system for saline wastewater, comprising a heat collection shed, a hot chimney, and an evaporation interface; the evaporation interface is used to cover the surface of the saline wastewater; the heat collection shed is used to cover the saline wastewater; and a hot chimney is installed on the heat collection shed.
[0020] The evaporation interface is the cellulose-based fabric photothermal material described in the above technical solution or the cellulose-based fabric photothermal material prepared by the preparation method described in the above technical solution.
[0021] This invention provides a cellulose-based fabric photothermal material, comprising: a cellulose fiber fabric, polyphenol metal coordination complexes and silver nanoparticles loaded on the surface and pores of the cellulose fiber fabric; the polyphenol metal complexes include polyphenol copper complexes, polyphenol ferric complexes, and polyphenol silver complexes. The cellulose-based fabric photothermal material provided by this invention exhibits strong light absorption performance in the visible light range, with a solar-to-water vapor conversion efficiency reaching 95.2%, effectively converting light energy into heat energy, demonstrating excellent photothermal conversion performance. Furthermore, after a 20-day cyclic experiment, the evaporation rate showed little fluctuation, no obvious salt scaling appeared on the material surface, and the water evaporation rate remained stable, allowing for reuse. In addition, an antibacterial zone experiment was conducted on the material, observing the appearance of an antibacterial zone around the material, indicating that the material possesses certain antibacterial properties.
[0022] The present invention also provides a method for preparing the above-mentioned cellulose-based fabric photothermal material. The photothermal composite material is generated on the cellulose-based fabric by a simple soaking and coordination reduction method. The preparation process is simple, the preparation cost is low, and it is easy to prepare on a large scale.
[0023] This invention also provides the application of the aforementioned cellulose-based fabric photothermal material in a thermal management enhanced interface concentration system for saline wastewater. The evaporation rate is further enhanced by constructing a hot chimney evaporation system. Sunlight irradiates the solar collector, and the evaporation interface beneath the collector absorbs solar radiation energy transmitted through the covering layer, heating the air between the water surface and the collector cover layer. This causes the air temperature inside the collector to rise, its density to decrease, and it to rise along the chimney. Dry air surrounding the collector enters the system, creating a high-temperature air circulation flow. This increases the water vapor partial pressure difference between the water interface and the high-temperature dry air, thereby further enhancing the evaporation of brine. This invention reduces heat loss at the evaporation interface through the hot chimney structure and evaporation system, utilizing the thermal pressure generated by the hot chimney to continuously circulate air, achieving an enhanced interface evaporation effect. Tests show that the cellulose-based fabric photothermal material prepared by this invention has good wettability and air permeability during evaporation. Under one day of sunlight, the water evaporation rate of the cellulose-based fabric photothermal material can reach 1.43 kgm³. -2 h -1 In a hot chimney system, the water evaporation rate can reach 2.52 kgm³. -2 h -1 The solar-to-water vapor conversion efficiency is as high as 95.2%. Attached Figure Description
[0024] Figure 1 A schematic diagram of an interface concentration system for enhanced thermal management of saline wastewater.
[0025] Figure 2 This is a scanning electron microscope image of the pure cotton cloth used in Example 1;
[0026] Figure 3 This is a scanning electron microscope image of the Cu-TA-Fe-Ag composite photothermal material prepared in Example 1;
[0027] Figure 4 Scanning electron microscope image of the Cu-TA-Fe composite photothermal material prepared in Comparative Example 1;
[0028] Figure 5 Scanning electron microscope image of the Cu-TA composite photothermal material prepared in Comparative Example 2;
[0029] Figure 6 Scanning electron microscope image of the Cu composite photothermal material prepared in Comparative Example 3;
[0030] Figure 7 The figure shows the stability test results of the Cu-TA-Fe-Ag composite photothermal material prepared in Example 1;
[0031] Figure 8 The image shows the Vis-NIR absorption spectrum of the Cu-TA-Fe-Ag composite photothermal material prepared in Example 1. Detailed Implementation
[0032] This invention provides a cellulose-based fabric photothermal material, comprising: cellulose fiber fabric, a polyphenol metal coordination complex and silver nanoparticles loaded on the surface and pores of the cellulose fiber fabric;
[0033] The polyphenol metal complexes include polyphenol copper complexes, polyphenol trivalent iron complexes, and polyphenol silver complexes.
[0034] Unless otherwise specified, the present invention does not have special requirements on the source of raw materials used, and commercially available products well known to those skilled in the art can be used.
[0035] The cellulose-based fabric photothermal material provided by this invention includes: cellulose fiber fabric. In this invention, the cellulose fiber fabric preferably includes one or more of cotton cellulose fiber fabric, hemp cellulose fiber fabric, and wood cellulose fiber fabric, more preferably cotton cellulose fiber fabric; the cotton cellulose fiber fabric is preferably cotton cloth; the thickness of the cellulose fiber fabric is preferably 1~5 cm, more preferably 2~3 cm.
[0036] The cellulose-based fabric photothermal material provided by the present invention comprises: polyphenol metal coordination complexes and silver nanoparticles loaded on the surface and pores of the cellulose fiber fabric; the polyphenol metal complexes include polyphenol copper complexes, polyphenol trivalent iron complexes and polyphenol silver complexes.
[0037] In this invention, the mass percentage of the polyphenol copper complex in the cellulose-based fabric photothermal material is preferably 1-5%, more preferably 2-3%, the mass percentage of the polyphenol trivalent iron complex is preferably 1-5%, more preferably 2-4%, the mass percentage of the polyphenol silver complex is preferably 1-5%, more preferably 2-3%, and the mass percentage of the silver nanoparticles is preferably 2-5%, more preferably 3-4%.
[0038] The cellulose-based fabric photothermal material provided by this invention has good stability, excellent photothermal performance, and antibacterial properties.
[0039] The present invention also provides a method for preparing the cellulose-based fabric photothermal material described in the above technical solution, comprising the following steps:
[0040] Cellulose fiber fabric is sequentially immersed in alkaline copper salt solution, polyphenol solution, soluble iron salt solution and soluble silver salt solution, and then washed and dried to obtain cellulose-based fabric photothermal material.
[0041] In this invention, cellulose fiber fabric is sequentially immersed in an alkaline copper salt solution, a polyphenol solution, a soluble iron salt solution, and a soluble silver salt solution.
[0042] In this invention, the alkaline copper salt solution is preferably a mixed solution of copper salt and sodium hydroxide; the copper salt preferably includes one or more of copper chloride, copper nitrate and copper sulfate, more preferably copper chloride; the sodium hydroxide preferably includes sodium hydroxide and / or potassium hydroxide, more preferably sodium hydroxide; the molar ratio of copper salt to sodium hydroxide is preferably 1:1 to 400, more preferably 1:200 to 350; the immersion time in the alkaline copper salt solution is preferably 12 to 24 hours, more preferably 15 to 20 hours.
[0043] In this invention, the preferred method for preparing the copper salt solution is to mix copper salt and water and then subject the mixture to ultrasonic treatment to obtain the copper salt solution; the ultrasonic treatment is performed at room temperature; the power of the ultrasonic treatment is preferably 10~450W, more preferably 100~300W; the duration of the ultrasonic treatment is preferably 5~20min, more preferably 10~15min; and the concentration of copper salt in the copper salt solution is preferably 1~3g / L, more preferably 1g / L.
[0044] In this invention, the preferred method for preparing the sodium hydroxide solution is to mix sodium hydroxide and water and then subject the mixture to ultrasonic treatment to obtain the sodium hydroxide solution; the ultrasonic treatment is performed at room temperature; the power of the ultrasonic treatment is preferably 10~450W, more preferably 100~300W; the duration of the ultrasonic treatment is preferably 5~20 min, more preferably 10~15 min; and the mass concentration of sodium hydroxide in the sodium hydroxide solution is preferably 5~20%, more preferably 10~15%.
[0045] In this invention, the preferred method for preparing the mixed solution of copper salt and sodium hydroxide is to mix the copper salt solution and the sodium hydroxide solution and then perform ultrasonic treatment at room temperature to obtain the mixed solution of copper salt and sodium hydroxide; the power of the ultrasonic treatment is preferably 10~450W, more preferably 100~300W; the ultrasonic treatment time is preferably 5~20 min, more preferably 10~15 min.
[0046] Before impregnation, the present invention preferably soaks the cellulose fiber fabric in ethanol to remove impurities, and then washes and dries it in sequence; the soaking time is preferably 10-60 min, more preferably 20-30 min; the washing is preferably done with deionized water; the drying is preferably done at room temperature; the drying time is preferably 5 min-3 h, more preferably 10 min-3 h.
[0047] After the immersion in the alkaline copper salt solution is completed, the present invention preferably washes the immersed cellulose fiber fabric with water until it is neutral; the washing is preferably performed with deionized water.
[0048] This invention involves immersing cellulose fiber fabric in an alkaline copper salt solution. First, the hydrogen bond network connecting the cellulose chains is disrupted in the alkaline environment. Then, Cu ions diffuse into the expanded cellulose material, allowing them to combine with the hydroxyl groups on the cellulose chains to form a stable copper ion-cellulose complex.
[0049] In this invention, the preferred method for preparing the polyphenol solution is to mix polyphenols and water and then subject the mixture to ultrasonic treatment to obtain the polyphenol solution; the ultrasonic treatment is performed at room temperature; the power of the ultrasonic treatment is preferably 10~450 W, more preferably 100~300 W; the duration of the ultrasonic treatment is preferably 5~20 min, more preferably 10~15 min.
[0050] In this invention, the polyphenols in the polyphenol solution preferably include one or more of tannic acid, phenol-ketone polyphenols and phenylpropane polyphenols, more preferably tannic acid; the concentration of the polyphenols in the polyphenol solution is preferably 2~4 g / L, more preferably 1~3 g / L; the immersion time in the polyphenol solution is preferably 1~4 h, more preferably 2 h.
[0051] After the polyphenol solution is impregnated, the present invention preferably washes the impregnated cellulose fiber fabric with water; the washing is preferably performed with deionized water.
[0052] This invention involves immersing a copper-loaded cellulose fiber fabric in a polyphenol solution. The natural polyphenol containing a catechol structure can provide lone pairs of electrons and form chelates with Cu(II) ions. Therefore, the polyphenols and copper ions form complexes through coordination.
[0053] In this invention, the soluble iron salt in the soluble iron salt solution preferably includes one or more of ferric chloride, ferric sulfate, and ferric nitrate, more preferably ferric chloride; the concentration of the soluble iron salt in the soluble iron salt solution is preferably 0.5~3 g / L, more preferably 1~2 g / L; the immersion time in the soluble iron salt solution is preferably 1~4 h, more preferably 2~3 h.
[0054] In this invention, the preferred method for preparing the soluble iron salt solution is to mix soluble iron salt and water and then subject the mixture to ultrasonic treatment to obtain the soluble iron salt solution; the ultrasonic treatment is performed at room temperature; the power of the ultrasonic treatment is preferably 10~450 W, more preferably 100~300 W; the duration of the ultrasonic treatment is preferably 5~20 min, more preferably 10~15 min.
[0055] After the immersion in the soluble iron salt solution is completed, the present invention preferably washes the immersed cellulose fiber fabric with water; the washing is preferably performed with deionized water.
[0056] In this invention, cellulose fiber fabric loaded with polyphenol-copper ion complex is impregnated in a soluble iron salt solution. The benzene ring in the polyphenol structure has two adjacent phenolic hydroxyl groups, which can undergo a complexation reaction with iron ions in the form of oxygen anions to form a chemically stable five-membered ring complex. Therefore, polyphenols and ferric ions form a complex through coordination.
[0057] In this invention, the soluble silver salt in the soluble silver salt solution preferably includes one or more of silver nitrate and silver ammonia; the concentration of the soluble silver salt in the soluble silver salt solution is preferably 0.5~4 g / L, more preferably 1~3 g / L; the immersion time in the soluble silver salt solution is preferably 6~24 h, more preferably 10~20 h.
[0058] In this invention, the preferred method for preparing the soluble silver salt solution is to mix soluble silver salt and water and then subject the mixture to ultrasonic treatment to obtain the soluble silver salt solution; the ultrasonic treatment is performed at room temperature; the power of the ultrasonic treatment is preferably 10~450 W, more preferably 100~300 W; the duration of the ultrasonic treatment is preferably 5~20 min, more preferably 10~15 min.
[0059] In this invention, cellulose fiber fabric loaded with polyphenol-copper ion-ferric ion complex is impregnated with a soluble silver salt solution. When there are at least two adjacent phenolic hydroxyl groups on the benzene ring in the polyphenol structure, the phenolic hydroxyl groups can chelate with silver ions. Therefore, some silver ions and polyphenols form complexes through coordination, and some anions are reduced by the phenolic hydroxyl groups in the polyphenols to form silver nanoparticles.
[0060] After the immersion in the soluble silver salt solution is completed, the cellulose fiber fabric is sequentially washed and dried to obtain a cellulose-based photothermal material. In this invention, the washing is preferably performed with deionized water; the drying time is preferably 5 min to 3 h, more preferably 10 min to 3 h; and the drying temperature is preferably room temperature.
[0061] This invention generates photothermal composite materials on cellulose substrates through a simple soaking and coordination reduction method. The preparation process is simple, the preparation cost is low, and it is easy to scale up.
[0062] The present invention also provides the application of the cellulose-based fabric photothermal material described in the above technical solution or the cellulose-based fabric photothermal material prepared by the preparation method described in the above technical solution in the treatment of saline wastewater.
[0063] The present invention also provides a thermal management enhanced interface concentration system for saline wastewater, comprising a heat collection shed, a hot chimney, and an evaporation interface; the evaporation interface is used to cover the surface of the saline wastewater; the heat collection shed is used to cover the saline wastewater; a hot chimney is provided on the heat collection shed; the evaporation interface is the cellulose-based fabric photothermal material described in the above technical solution or the cellulose-based fabric photothermal material prepared by the preparation method described in the above technical solution.
[0064] In this invention, the distance between the heat collection shed and the evaporation interface is preferably 3 to 10 cm, and more preferably 5 to 8 cm.
[0065] Figure 1 A schematic diagram of an interface concentration system for enhanced thermal management of saline wastewater. Figure 1 As shown, the saline wastewater thermal management enhanced interface concentration system includes a heat collection shed, a hot chimney, and an evaporation interface (cellulose-based fabric photothermal material); the evaporation interface is used to cover the surface of the saline wastewater; the heat collection shed is used to cover the saline wastewater; and a hot chimney is installed on the heat collection shed.
[0066] This invention further enhances the evaporation rate by constructing a hot chimney evaporation system. Sunlight illuminates the solar collector, and the evaporation interface beneath the collector absorbs solar radiation energy transmitted through the covering layer, heating the air between the water surface and the collector's covering layer. This causes the air temperature inside the collector to rise, its density to decrease, and it to rise along the chimney. Dry air surrounding the collector enters the system, creating a high-temperature air circulation flow. This increases the water vapor partial pressure difference between the water interface and the high-temperature dry air, further enhancing the evaporation of the brine. This invention reduces heat loss at the evaporation interface through the hot chimney structure and evaporation system, utilizing the thermal pressure generated by the hot chimney to continuously circulate air, achieving a more efficient interface evaporation effect. Tests show that the cellulose-based fabric photothermal material prepared by this invention exhibits good wettability and air permeability during evaporation. Under one day of sunlight, the water evaporation rate of the cellulose-based fabric photothermal material can reach 1.43 kg / m³. -2 h -1 In a hot chimney system, the water evaporation rate can reach 2.52 kg / m³. - 2 h -1 The solar-to-water vapor conversion efficiency is as high as 95.2%.
[0067] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, but they should not be construed as limiting the scope of protection of the present invention.
[0068] Example 1
[0069] 1) Preparation of solution
[0070] Dissolve 10 g of sodium hydroxide in 90 mL of deionized water and sonicate at 300 W for 10 min at room temperature. After sonication, prepare a 10 wt% sodium hydroxide solution.
[0071] Dissolve 0.1 g of copper chloride in 100 mL of deionized water and sonicate at 300 W for 10 min at room temperature. After sonication, a copper chloride solution with a concentration of 1 g / L is obtained. Mix the sodium hydroxide solution and the copper chloride solution evenly and sonicate at 300 W for 10 min at room temperature to prepare a mixed solution of sodium hydroxide and copper chloride, i.e., an alkaline copper salt solution.
[0072] Dissolve 0.2 g of tannic acid (TA) in 100 mL of deionized water and sonicate at 300 W for 10 min at room temperature to prepare a 2 g / L TA solution for later use.
[0073] Dissolve 0.1 g of anhydrous ferric chloride in 100 mL of deionized water, and sonicate at 300 W for 10 min at room temperature to prepare a ferric chloride solution with a concentration of 1 g / L for later use.
[0074] Dissolve 0.1g of silver chloride in 100 mL of deionized water and sonicate at 300 W for 10 min at room temperature to prepare a silver chloride solution with a concentration of 1g / L for later use.
[0075] 2) Preparation of cellulose-based fabric photothermal materials
[0076] The cotton cloth was soaked in ethanol for 30 minutes to remove impurities, then washed with deionized water and dried at room temperature for 3 hours before use.
[0077] After washing, the cotton fabric was soaked in an alkaline copper salt solution for 24 hours, washed with deionized water until neutral, and then soaked in a TA solution for 2 hours. After washing with deionized water, the cotton fabric was soaked in a ferric chloride solution for 1 hour. The cotton fabric was then removed, washed with deionized water, and then soaked in a silver chloride solution for 12 hours. Finally, after repeated washing with deionized water, it was dried at room temperature for 3 hours to obtain a cellulose-based fabric photothermal material, namely a Cu-TA-Fe-Ag composite photothermal material.
[0078] Comparative Example 1
[0079] The preparation process is the same as in Example 1, except that the soaking in silver chloride solution is reduced to obtain Cu-TA-Fe composite photothermal material.
[0080] Comparative Example 2
[0081] The preparation process is the same as in Example 1, except that the immersion in ferric chloride solution and silver chloride solution is reduced to obtain Cu-TA composite photothermal material.
[0082] Comparative Example 3
[0083] The preparation process is the same as in Example 1, except that the immersion in TA solution, ferric chloride and silver chloride solution is reduced to obtain Cu composite photothermal material.
[0084] Application Example 1
[0085] A thermal management enhanced interface concentration system for saline wastewater includes a heat collection shed, a hot chimney, and an evaporation interface; the evaporation interface covers the surface of the saline wastewater; the heat collection shed covers the saline wastewater; a hot chimney is set in the center of the heat collection shed; the evaporation interface is a cellulose-based fabric photothermal material prepared in Example 1, and the distance between the heat collection shed and the evaporation interface is 5 cm.
[0086] Application Example 2
[0087] The difference from Application Example 1 is that the distance between the heat collection shed and the evaporation interface is 10cm.
[0088] Comparative Application Example 1
[0089] The difference from Application Example 1 is that the evaporation interface is the Cu-TA-Fe composite photothermal material prepared in Comparative Example 1.
[0090] Comparative Application Example 2
[0091] The difference from Application Example 1 is that the evaporation interface is the Cu-TA composite photothermal material prepared in Comparative Example 2.
[0092] Comparative Application Example 3
[0093] The difference from Application Example 1 is that the evaporation interface is the Cu composite photothermal material prepared in Comparative Example 3.
[0094] Performance testing
[0095] (1) The water evaporation rate of the composite photothermal materials prepared in Example 1 and Comparative Examples 1-3 was tested. The experimental climatic conditions included: humidity 35%, air temperature 20℃, water temperature 20℃, wind speed 2m / s, and solar irradiance 1kW / m. The results are shown in Table 1.
[0096] Table 1. Water evaporation rates of the composite photothermal materials prepared in Example 1 and Comparative Examples 1-3
[0097]
[0098] As shown in Table 1, the water evaporation rate of the Cu-TA-Fe-Ag composite photothermal material prepared in Example 1 is higher than that of the Cu-TA-Fe composite photothermal material prepared in Comparative Example 1, and higher than that of the Cu-TA composite photothermal material prepared in Comparative Example 2. That is, the water evaporation rate of the Cu-TA-Fe-Ag composite photothermal material is the best.
[0099] (2) The water evaporation rate and solar-water vapor conversion efficiency of the saline wastewater thermal management enhanced interface concentration system prepared in corresponding use cases 1-2 and comparative application examples 1-3 were tested. The climatic conditions of the experiment included: humidity 35%, air temperature 20℃, water temperature 20℃, wind speed 2m / s, and solar irradiance 1kW / m. The results are shown in Table 2.
[0100] Table 2. Water evaporation rate and solar-to-water vapor conversion efficiency in the thermal management enhanced interface concentration system for saline wastewater prepared in Application Examples 1-2 and Comparative Application Examples 1-3.
[0101]
[0102] As shown in Table 2, Application Example 1 has the highest water evaporation rate and solar-to-water vapor conversion efficiency, making it the optimal solution. This is achieved by using the prepared Cu-TA-Fe-Ag composite photothermal material and setting the distance between the collector and the evaporation interface to be 5 cm.
[0103] (3) Scanning electron microscopy tests were performed on the pure cotton cloth used in Example 1, the prepared Cu-TA-Fe-Ag composite photothermal material, the Cu-TA-Fe composite photothermal material prepared in Comparative Example 1, the Cu-TA composite photothermal material prepared in Comparative Example 2, and the Cu composite photothermal material prepared in Comparative Example 3. The results are as follows: Figures 2-6 As shown.
[0104] Depend on Figures 2-6 It can be seen that, compared with pure cotton cloth and Cu composite photothermal material prepared in Comparative Example 3, Cu-TA composite photothermal material prepared in Comparative Example 2, Cu-TA-Fe composite photothermal material prepared in Comparative Example 1, and Cu-TA-Fe-Ag composite photothermal material prepared in Example 1 all showed particles. Among them, the prepared Cu-TA-Fe-Ag composite photothermal material had the densest particles. The metal particle loading is beneficial to the photothermal conversion efficiency and improves its evaporation efficiency.
[0105] (4) The stability of the Cu-TA-Fe-Ag composite photothermal material prepared in Example 1 was tested, and the results are as follows: Figure 7As shown in the figure, the water evaporation rate of the Cu-TA-Fe-Ag composite photothermal material prepared by this invention remained stable after a 20-day cycle experiment, with little fluctuation. Furthermore, no obvious salt scaling was observed on the material surface, indicating that the Cu-TA-Fe-Ag composite photothermal material prepared by this invention is stable and can be reused.
[0106] (5) Figure 8 The image shows the Vis-NIR absorption spectrum of the Cu-TA-Fe-Ag composite photothermal material prepared in Example 1. As can be seen from the image, the Cu-TA-Fe-Ag composite photothermal material prepared in this invention exhibits strong light absorption performance in the visible light range, while achieving a solar energy conversion efficiency of 95.2%.
[0107] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.
Claims
1. The application of cellulose-based fabric photothermal materials in the treatment of saline wastewater, characterized in that, The cellulose-based fabric photothermal material is composed of cellulose fiber fabric, polyphenol metal coordination complexes and silver nanoparticles loaded on the surface and pores of the cellulose fiber fabric. The polyphenol metal coordination complex is composed of a polyphenol copper complex, a polyphenol trivalent iron complex, and a polyphenol silver complex. The cellulose-based fabric photothermal material contains 1-5% by mass of copper polyphenol complex, 1-5% by mass of iron polyphenol complex, 1-5% by mass of silver polyphenol complex, and 2-5% by mass of silver nanoparticles. The preparation method of the cellulose-based fabric photothermal material includes the following steps: Cellulose fiber fabric is sequentially immersed in alkaline copper salt solution, polyphenol solution, soluble iron salt solution and soluble silver salt solution, and then washed and dried to obtain cellulose-based fabric photothermal material.
2. The application according to claim 1, characterized in that, The cellulose fiber fabric is selected from one or more of cotton cellulose fiber fabric, hemp cellulose fiber fabric and wood cellulose fiber fabric.
3. The application according to claim 1, characterized in that, The alkaline copper salt solution is a mixed solution of copper salt and sodium hydroxide; the molar ratio of copper salt to sodium hydroxide is 1:1 to 400.
4. The application according to claim 3, characterized in that, The copper salt is selected from one or more of copper chloride, copper nitrate and copper sulfate.
5. The application according to claim 1, characterized in that, The polyphenols in the polyphenol solution are selected from one or more of tannic acid and phenylpropane polyphenols; the concentration of the polyphenols in the polyphenol solution is 2~4 g / L.
6. The application according to claim 1, characterized in that, The soluble iron salt in the soluble iron salt solution is selected from one or more of ferric chloride, ferric sulfate, and ferric nitrate; the concentration of the soluble iron salt in the soluble iron salt solution is 0.5~3g / L.
7. A thermal management-enhanced interface concentration system for saline wastewater, characterized in that, It includes a heat collection shed, a hot chimney, and an evaporation interface; the evaporation interface is used to cover the surface of saline wastewater; the heat collection shed is used to cover the saline wastewater; and a hot chimney is installed on the heat collection shed. The evaporation interface is the cellulose-based fabric photothermal material used in any one of claims 1 to 6.