Preparation method and application of super-hydrophobic super-oleophylic oil-water separation tin bronze net
Through selective chemical etching and gas phase modification process, a super-hydrophobic and super-oleophilic interface is formed on the tin-bronze mesh, which solves the problem that the tin-bronze mesh does not have the oil-water separation function and realizes efficient and stable large-scale production and separation effects.
Patent Information
- Application Number
- CN202511003987.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-21
- Publication Date
- 2025-09-23
AI Technical Summary
The existing tin bronze mesh does not have the oil-water separation function, and traditional liquid phase modification methods make it difficult to achieve large-scale and stable production of superhydrophobic and superoleophilic materials.
A selective chemical etching and vapor phase surface modification collaborative process was adopted. The tin bronze mesh was etched with a hydrochloric acid-alcohol-copper corrosion inhibitor mixture, and aldehyde gas was used for chemical grafting in a vapor phase environment to form a superhydrophobic and superoleophilic interface.
A super-hydrophobic and super-oleophilic tin bronze mesh with high separation efficiency, wide range and good stability was prepared. It can efficiently separate oily wastewater, is corrosion-resistant, and is suitable for large-scale production.
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Figure CN120681836A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of oily wastewater separation materials, and in particular relates to a preparation method and application of a super-hydrophobic and super-oleophilic oil-water separation tin bronze mesh. Background Art
[0002] Marine oil spills, oily wastewater discharged from chemical industry and daily life have caused water pollution. Therefore, the development of technologies and methods for collecting oil from the water surface has become a very urgent task. Inspired by nature, porous materials with completely opposite wettability to water and oil provide a simple and effective method for removing oil from the water surface. In the past two decades, a large number of porous materials with completely opposite wettability to water and oil have been prepared for oil-water separation. In order to better solve the problem of oil-water separation in industry, it is necessary to prepare stable materials simply and on a large scale. Among them, meshes with a contact angle with water greater than 150° (sliding angle less than 10°) and a contact angle with oil less than 10° are considered to be superhydrophobic and superoleophilic oil-water separation materials.
[0003] Tin bronze mesh, with its excellent flexibility and permeability, is an ideal substrate for oil-water separation. However, commercially available tin bronze mesh itself lacks oil-water separation capabilities, requiring etching or modification to create micro- / nanostructures and reduce surface energy to achieve opposite wettability to oil and water. To achieve super-hydrophobic and super-oleophilic tin bronze mesh membranes, the surface of the tin bronze mesh is typically modified with low-surface-energy materials such as stearic acid or perfluorosilane.
[0004] Unlike conventional methods of simply etching with strong acids or modifying surfaces with solutions, this method proposes a collaborative process based on selective chemical etching and vapor-phase surface modification. This involves controllably etching the tin-bronze mesh using a hydrochloric acid-alcohol-copper corrosion inhibitor mixture. Furthermore, aldehyde gases are used to chemically graft the surface molecular layer in a vapor-phase environment, forming a superhydrophobic and superoleophilic interface that is firmly bonded to the metal substrate. This method overcomes the limitations of traditional liquid-phase modification, achieving an integrated process from substrate surface structure control to functional layer construction, providing a new solution for the large-scale production of highly stable oil-water separation membranes. Summary of the Invention
[0005] The purpose of the present invention is to provide a super-hydrophobic and super-oleophilic tin-bronze mesh oily wastewater separation filter membrane with high separation efficiency, wide separation range and stable separation effect.
[0006] In order to achieve the above object, the technical solution adopted by the present invention is:
[0007] A method for preparing a super-hydrophobic and super-oleophilic tin bronze mesh oily wastewater separation filter membrane comprises the following steps:
[0008] (1) A commercially available thickened tin bronze mesh with micron-sized mesh is cut into the required size, ultrasonically cleaned in ethanol and deionized water to remove surface stains, and then dried at room temperature. The cleaned tin bronze mesh is then placed in a mixture of hydrochloric acid, alcohol, and copper corrosion inhibitor to selectively etch the surface. After etching, the mesh is thoroughly washed with hydrochloric acid and distilled water to remove surface residues such as copper corrosion inhibitor; and then quickly dried with cold air to ensure that there is no residual water film on the surface.
[0009] (2) Add liquid or solid unsaturated aldehyde as a steam source into a sealed glass container, wait until the steam environment is stable at room temperature, and then place the tin bronze mesh dried by cold air in the aldehyde vapor containing air. In air, the contact angle between water and the surface of the obtained tin bronze mesh is greater than 160°, the rolling angle is less than 3°, and the contact angle between oil and its surface is about 0°. By utilizing this diametrically opposite wetting property for oil and water, the obtained tin bronze mesh can separate oily wastewater. Preferably: the tin bronze mesh in step (1) is 100-400 mesh, and its main components are Cu 1-x Sn x (containing tin x = 5-20%); the pretreatment specifically comprises ultrasonically removing stains on the surface of the tin bronze mesh using ethanol and deionized water, respectively, with the ultrasonic time being 10 minutes each, and then drying at room temperature.
[0010] Preferably: the mass percentage concentration of hydrochloric acid used in the step (1) for etching and cleaning the bronze mesh is 20-30%, the mass percentage concentration of alcohol is 1-5%, the mass percentage concentration of copper corrosion inhibitor is 0.1-0.5%, the alcohol is one or more of ethanol, n-propanol, ethylene glycol, glycerol, 1,2-propylene glycol, and 1,3-propylene glycol, the copper corrosion inhibitor is one of benzotriazole, methylbenzotriazole, mercaptobenzothiazole, and 2-mercaptobenzoxazole, the etching time is 2-24 hours, and the temperature is 20-60°C.
[0011] Preferably: the tin bronze mesh obtained in the step (2) is placed in an aldehyde atmosphere containing air at room temperature for 4-8 hours, and the aldehyde used includes but is not limited to unsaturated aldehyde compounds such as benzaldehyde, p-4-methylbenzaldehyde, 4-isopropylbenzaldehyde, citral, 2-heptenal, undecenal, 2-nonenal, 2-hexenal, 9-decenal, and 2-tridecenal; unsaturated carboxylic acid copper is generated on the surface, and the surface wettability of the tin bronze mesh gradually changes from superhydrophilic to superhydrophobic, while the superoleophilicity remains unchanged. Unsaturated carboxylic acid copper is generated on the surface, and the surface wettability of the tin bronze mesh gradually changes from superhydrophilic to superhydrophobic, while the superoleophilicity remains unchanged.
[0012] Preferably, in air, the contact angle with water is greater than 160°, the rolling angle is less than 3°, and the contact angle with oil is approximately 0°. Utilizing these opposite wetting properties for oil and water, the resulting tin-bronze mesh can effectively separate oily wastewater.
[0013] Preferably, when separating an oil-water mixture, a water-diesel mixture was poured into a beaker and a "microboat" made of tin-bronze mesh was placed inside. The diesel quickly permeated the "microboat" and flowed into it, while the water remained outside, drawing the diesel away from the "microboat." This demonstrates that the "microboat" can easily separate the oil-water mixture. The oil in the oil-water mixture was at least one of petroleum ether, n-hexane, cyclohexane, benzene, toluene, xylene, nitrobenzene, gasoline, kerosene, diesel, peanut oil, sesame oil, olive oil, dichloromethane, chloroform, dichloroethane, and carbon tetrachloride, achieving a separation efficiency of up to 99.3%.
[0014] Oily wastewater discharged from industrial wastewater often contains corrosive components. To treat this type of wastewater, the prepared samples must be corrosion-resistant. For pH 3-11 solutions and 3% sodium chloride solutions, the contact angle of a water droplet on the resulting tin-bronze mesh remained consistently above 160° after 30 minutes.
[0015] The advantages of the present invention are:
[0016] 1. The super-hydrophobic and super-oleophilic tin-bronze mesh for oil-water separation provided by the present invention only needs to be rapidly detinned and aged in aldehyde to achieve super-hydrophobic and super-oleophilic properties. In air, the contact angle with water is greater than 160°, the rolling angle is less than 3°, and the contact angle between water and oil is approximately 0°. Utilizing these diametrically opposed wetting properties for oil and water phases, the resulting tin-bronze mesh can effectively separate oily wastewater.
[0017] 2. The super-hydrophobic and super-oleophilic tin-bronze mesh for oil-water separation provided by the present invention maintained an oil-water contact angle of more than 160° and a separation efficiency of more than 99.3% after separating a diesel-water mixture 60 times.
[0018] 3. Oily wastewater discharged from industrial wastewater often contains corrosive components. To treat this type of wastewater, the prepared sample must be corrosion-resistant. For pH 3-11 solutions and 3% sodium chloride solutions, the contact angle of a water droplet on the resulting tin-bronze mesh remained consistently above 160° after 30 minutes.
[0019] 4. The process of the present invention is simple, suitable for large-scale production, does not require the use of special equipment, and the processing process is easy to implement. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 SEM images of (a) pristine tin-bronze mesh and (bd) aged tin-bronze mesh in benzaldehyde atmosphere containing air.
[0021] Figure 2 This is an SEM image of a cross section of a single brass wire of an aged tin-bronze mesh;
[0022] Figure 3These are the XRD patterns of the original, detinned, and aged tin bronze mesh surfaces; the horizontal axis represents degree, and the vertical axis represents intensity.
[0023] Figure 4 EDS spectra of (a) original brass mesh, (b) detinned brass mesh, and (c) aged brass mesh in benzaldehyde atmosphere containing air; the horizontal axis is energy, the vertical axis is count rate, Element is element, and wt% is weight percentage.
[0024] Figure 5 are the ATR-FTIR spectra of the original, detinned, and aged tin-bronze meshes in benzaldehyde atmosphere containing air;
[0025] In the figure, the horizontal axis is the wave number and the vertical axis is the transmittance.
[0026] Figure 6 These are the Raman spectra of the original, detinned, and aged tin-bronze mesh in a benzaldehyde atmosphere containing air; the horizontal axis is the Raman shift and the vertical axis is the intensity.
[0027] Figure 7 These are the XPS spectra of the original, detinned, aged tin bronze mesh in benzaldehyde and benzoic acid atmosphere containing air; the horizontal axis is the binding energy and the vertical axis is the intensity.
[0028] Figure 8 The contact angles of (a) water on a tin-bronze mesh aged in an atmosphere of benzaldehyde containing air and (b)
[0029] The rolling angle of water;
[0030] Figure 9 It is the dynamic wetting behavior of kerosene droplets in air on an aged tin-bronze mesh in an atmosphere of benzaldehyde containing air;
[0031] Figure 10 (a) A "micro boat" prepared by bending an aged tin bronze mesh in a benzaldehyde atmosphere containing air.
[0032] (bd) The process of separating diesel from water using a "microboat".
[0033] Figure 11 The contact angle of water with aged tin bronze mesh in benzaldehyde atmosphere containing air changes with pH value. Figure 12 . is the contact angle of a water droplet of 3% NaCl solution on an aged tin bronze mesh in an atmosphere of benzaldehyde containing air. DETAILED DESCRIPTION
[0034] Example 1
[0035] A 400-mesh tin bronze mesh (93.31% Cu, 6.27% Sn, and the remainder is other metals) was purchased and cut into 5cm×5cm sizes. It was ultrasonically treated with ethanol and deionized water at room temperature for 10 minutes to remove stains attached to the surface, and then dried at room temperature. It was immersed in an aqueous solution of 30% hydrochloric acid, 5.0% ethanol, and 0.5% benzotriazole by mass. Bubbles appeared on the surface of the tin bronze mesh, and it was detinned at room temperature for 24 hours. After etching, it was thoroughly washed with 30% hydrochloric acid and distilled water to remove surface residues such as copper corrosion inhibitors on the surface of the tin bronze mesh; and quickly dried with cold air to ensure that there was no residual water film on the surface. 10ml of liquid benzaldehyde was added to a 1L sealed glass container as a vapor source. After the steam environment stabilized at room temperature, the dried tin bronze mesh was placed in aldehyde vapor containing air for 6 hours to obtain a super-hydrophobic and super-oleophilic oil-water separation tin bronze mesh. The super hydrophobic and super oleophilic tin bronze mesh prepared by the above preparation method was observed by scanning electron microscopy. The results showed that the surface of the tin bronze mesh had a nano-scale pore structure, which together with the micron-scale mesh formed a rough tin bronze mesh surface ( Figure 1 , 2). The surface composition of the tin-bronze mesh was analyzed using XRD, EDS, FTIR, Raman and XPS spectra. Figure 3 、 4 Figures 7 and 8 indicate that the tin content decreases after hydrochloric acid etching, indicating that hydrochloric acid selectively removes some of the tin from the tin-bronze mesh: CuSn + 2HCl → Cu + SnCl2 + H2↑. During the hydrochloric acid etching process, the exposed copper reacts with dissolved oxygen to form cuprous oxide: 4Cu + O2 → 2Cu2O. Figure 3 、 4 , 6, and 7 indicate that the cuprous oxide generated during the hydrochloric acid etching process reacts with hydrochloric acid to generate cuprous chloride: Cu2O+2HCl→2CuCl+H2O. Figure 3 、 4 Figures 6 and 7 show that cuprous chloride formed on the surface of the tin-bronze mesh after hydrochloric acid etching reacts with water in the air at room temperature during the cold air drying process to form cuprous oxide: 2CuCl + H₂O → Cu₂O + 2HCl↑. In a closed aldehyde atmosphere containing air, cuprous oxide catalyzes the disproportionation reaction of benzaldehyde with oxygen in the sealed container: 2C₆H₅CHO + O₂ → C₆H₅COOH + C₆H₅CH₂OH. Figure 5 、 7 The results show that the generated benzoic acid reacts with Cu2O to form copper benzoate, 2C6H5COOH+Cu2O→2Cu+(C6H5COO)2Cu+H2O. The copper benzoate generated on the surface of the tin bronze mesh makes the contact angle of the obtained tin bronze mesh with water in air 165° and the rolling angle less than 3° ( Figure 8 ), while the contact angle with kerosene is about 0°( Figure 9). By utilizing the opposite wetting properties of oil and water, the obtained tin bronze mesh can effectively separate oily wastewater.
[0036] Simulating a ship collecting oil spills at sea, the super-hydrophobic and super-oleophilic tin-bronze mesh was used to separate the oil-water mixture ( Figure 10 ). When separating the oil-water mixture, a mixture of water and diesel was put into a beaker, and a "microboat" made of tin-bronze mesh was placed in the beaker. The diesel quickly penetrated the "microboat" and flowed into it, while the water remained outside the "microboat" and absorbed the diesel from the "microboat", which showed that the "microboat" could easily separate the oil-water mixture. We further calculated the oil-water separation efficiency of the "microboat" by collecting and weighing the oil collected by the "microboat". The separation efficiency is defined as the mass ratio of the oil collected from the beaker by the "microboat" to the oil in the original oil-water mixture. The oil in the oil-water mixture is one or more of petroleum ether, n-hexane, cyclohexane, benzene, toluene, xylene, nitrobenzene, gasoline, kerosene, diesel, peanut oil, sesame oil, olive oil, dichloromethane, chloroform, dichloroethane, and carbon tetrachloride. After the super-hydrophobic and super-oleophilic tin-bronze mesh separated the diesel-water mixture 50 times, the oil-water contact angle was still above 165°, and the separation efficiency was still higher than 99.3%, proving that the super-hydrophobic and super-oleophilic tin-bronze mesh has excellent reusability.
[0037] Oily wastewater discharged from industry often contains corrosive components. In order to treat this type of wastewater, the prepared samples must have corrosion resistance. The contact angles of droplets of different pH values and 3% NaCl solution on the tin bronze mesh surface are always higher than 163° (30 minutes after the droplets are placed on the tin bronze mesh surface). Figure 11 and Figure 12 ).
[0038] Example 2
[0039] A commercially available 300-mesh tin bronze mesh (93.31% Cu, 6.27% Sn, with the remainder being various other metals) was cut into 10 cm × 10 cm dimensions and ultrasonically treated with ethanol and deionized water for 10 minutes at room temperature to remove surface stains. The mesh was then air-dried at room temperature. The mesh was immersed in an aqueous solution of 25% hydrochloric acid, 3.0% n-propanol, and 0.3% methylbenzotriazole, resulting in bubbles on the surface. The mesh was then detinned at 40°C for 8 hours. After etching, the mesh was thoroughly washed with 25% hydrochloric acid and distilled water to remove surface residues such as copper corrosion inhibitors. The mesh was then quickly dried with cold air to ensure no residual water film remained on the surface. 10 ml of liquid styrylaldehyde was added to a 1 L sealed glass container as a vapor source. After the vapor environment stabilized at room temperature, the dried mesh was placed in an aldehyde vapor containing air for 6 hours to obtain a superhydrophobic and superoleophilic tin bronze mesh for oil-water separation. The contact angle of the obtained tin bronze mesh with water in air is 163°, and the rolling angle is less than 3° ( Figure 8 ), while the contact angle with oil is about 0°.
[0040] The surface composition of the obtained tin bronze mesh is similar to that of Example 1, and the oil-water mixture separation and acid, alkali and salt resistance are the same as those of Example 1.
[0041] Example 3
[0042] A commercially available 200-mesh tin bronze mesh (93.31% Cu, 6.27% Sn, with the remainder being various other metals) was cut into 15 cm x 15 cm pieces and ultrasonically treated with ethanol and deionized water for 10 minutes at room temperature to remove surface stains. The mesh was then air-dried at room temperature. The mesh was immersed in an aqueous solution of 20% hydrochloric acid, 1.0% ethylene glycol, and 0.2% mercaptobenzothiazole, resulting in bubbles on the surface. The mesh was then detinned at 60°C for 2 hours. After etching, the mesh was thoroughly washed with 20% hydrochloric acid and distilled water to remove surface residues such as copper corrosion inhibitors. The mesh was then quickly dried with cold air to ensure no residual water film remained on the surface. A 1 L sealed glass container was filled with 10 ml of liquid 4-methylbenzaldehyde as a vapor source. After the vapor environment stabilized at room temperature, the dried mesh was placed in an aldehyde vapor containing air for 6 hours to obtain a superhydrophobic and superoleophilic tin bronze mesh for oil-water separation. The contact angle of the obtained tin bronze mesh with water in air is 162°, and the rolling angle is less than 3° ( Figure 8 ), while the contact angle with oil is about 0°.
[0043] The surface composition of the obtained tin bronze mesh is similar to that of Example 1, and the oil-water mixture separation and acid, alkali and salt resistance are the same as those of Example 1.
Claims
1. A method for preparing a super-hydrophobic and super-oleophilic tin bronze mesh for oil-water separation, characterized in that: It consists of the following steps: (1) A commercially available thickened tin bronze mesh with micron-sized mesh is cut into the required size, ultrasonically washed in ethanol and deionized water to remove stains on the surface, and dried at room temperature; the cleaned tin bronze mesh is then placed in a mixture of hydrochloric acid, alcohol, and copper corrosion inhibitor to selectively etch the surface layer; after etching, it is thoroughly washed with hydrochloric acid and distilled water to remove surface residues such as copper corrosion inhibitor on the surface of the tin bronze mesh; and quickly dried with cold air to ensure that there is no residual water film on the surface; (2) Liquid or solid unsaturated aldehyde is added as a vapor source in a sealed glass container. After the vapor environment stabilizes at room temperature, the tin bronze mesh dried by cold air is placed in the aldehyde vapor containing air. In air, the contact angle between water and the surface of the obtained tin bronze mesh is greater than 160°, the rolling angle is less than 3°, while the contact angle between oil and its surface is about 0°. By utilizing this diametrically opposite wetting property of oil and water, the obtained tin bronze mesh can separate oily wastewater.
2. The method for preparing a super-hydrophobic and super-oleophilic oil-water separation tin bronze mesh as claimed in claim 1, wherein: The tin bronze mesh in step (1) is 100-400 mesh, mainly composed of Cu 1-x Sn x (containing tin x = 5-20%); the pretreatment specifically comprises ultrasonically removing stains on the surface of the tin bronze mesh using ethanol and deionized water, respectively, with the ultrasonic time being 10 minutes each, and then drying at room temperature.
3. The preparation method of the super-hydrophobic and super-oleophilic oil-water separation tin bronze mesh as claimed in claim 1, wherein: The mass percentage concentration of hydrochloric acid used in the step (1) for etching and cleaning the bronze mesh is 20-30%, the mass percentage concentration of alcohol is 1-5%, and the mass percentage concentration of copper corrosion inhibitor is 0.1-0.5%. The alcohol is one or more of ethanol, n-propanol, ethylene glycol, glycerol, 1,2-propylene glycol, and 1,3-propylene glycol. The copper corrosion inhibitor is one of benzotriazole, methylbenzotriazole, mercaptobenzothiazole, and 2-mercaptobenzoxazole. The etching time is 2-24 hours and the temperature is 20-60°C.
4. The method for preparing a super-hydrophobic and super-oleophilic oil-water separation tin bronze mesh as claimed in claim 1, wherein: The tin bronze mesh obtained in the step (2) is aged for 4-8 hours in an aldehyde atmosphere containing air at room temperature, wherein the aldehyde used includes but is not limited to unsaturated aldehyde compounds such as benzaldehyde, p-4-methylbenzaldehyde, 4-isopropylbenzaldehyde, citral, 2-heptenal, undecenal, 2-nonenal, 2-hexenal, 9-decenal, and 2-tridecenal; unsaturated copper carboxylate is generated on the surface, and the surface wettability of the tin bronze mesh gradually changes from superhydrophilic to superhydrophobic, while the superoleophilicity remains unchanged.
5. The super-hydrophobic and super-oleophilic tin bronze mesh for oil-water separation according to claim 1 is characterized in that: In air, the contact angle with water is greater than 160°, the rolling angle is less than 3°, and the contact angle with oil is about 0°. By utilizing this opposite wetting property of oil and water, the obtained tin bronze mesh can effectively separate oily wastewater.
6. The application of the super-hydrophobic and super-oleophilic oil-water separation tin bronze mesh oil-water separation filter membrane as claimed in claim 1, characterized in that: When separating an oil-water mixture, a mixture of water and diesel was poured into a beaker, and a "mini boat" made of tin-bronze mesh was placed in the beaker. The diesel quickly penetrated the "mini boat" and flowed into it, while the water remained outside the "mini boat" and absorbed the diesel from the "mini boat", indicating that the "mini boat" can easily separate the oil-water mixture; the oil in the oil-water mixture was at least one or more of petroleum ether, n-hexane, cyclohexane, benzene, toluene, xylene, nitrobenzene, gasoline, kerosene, diesel, peanut oil, sesame oil, olive oil, dichloromethane, chloroform, dichloroethane, and carbon tetrachloride, with a separation efficiency of up to 99.3%.
7. Oily wastewater discharged from industry often contains corrosive components. In order to treat this type of wastewater, the prepared samples must have corrosion resistance. For pH 3-11 solution and 3% NaCl solution, the contact angle of water droplets dropped on the surface of the obtained tin bronze mesh is always higher than 160° after 30 minutes.