Method for rapidly adsorbing heavy metal ions by using sulfydryl functionalized non-woven fabric

Abstract

The invention discloses a method for rapidly adsorbing heavy metal ions by a sulfydryl-functionalized non-woven fabric, relates to preparation of the sulfydryl-functionalized non-woven fabric and heavy metal adsorption application, and belongs to the technical field of functional materials and environmental protection. A catechol derivative, an oxidizing agent, a sulfur-containing coupling agent and the like are prepared into a reaction solution according to a certain proportion, then the non-woven fabric is immersed into the reaction solution for surface modification, the sulfydryl-functionalized non-woven fabric is prepared through reduction, and finally the sulfydryl-functionalized non-woven fabric is applied to adsorption and removal of heavy metal ions in water. The method has the advantages of being mild in condition, high in reaction speed and short in preparation period, the operation process is simple, universality is achieved, and the prepared functional material has the advantages of being good in heavy metal ion adsorption effect, good in functional modification layer stability and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of functional materials and environmental protection, and particularly relates to a method for preparing a mercapto-modified non-woven fabric and rapidly adsorbing heavy metal ions. BACKGROUND

[0002] Heavy metal pollution has the characteristics of carcinogenicity, teratogenicity, mutagenicity, and non-biodegradability. Therefore, it is of great significance to find an efficient and economical method to remove wastewater containing heavy metal ions.

[0003] At present, there are many technologies for the treatment of heavy metal ions in wastewater, including various physical and chemical methods, such as ion exchange method, chemical precipitation method, flocculation method, adsorption method and electrochemical method, etc. Ion exchange method, chemical precipitation method, flocculation method and electrochemical method have certain limitations in the treatment of wastewater containing heavy metals. The adsorption method is simple to operate, flexible in design, and has good effect on the removal of heavy metal ions, and has been widely concerned. In the adsorption process, the adsorption material is the key to the rapid and efficient treatment of heavy metal ions by adsorption method, so the preparation of the adsorption material is very important.

[0004] With the in-depth study of heavy metal pollution control, people gradually realized that single heavy metal pollution in an absolute sense does not exist, and heavy metal pollution is mostly associated and comprehensive, that is, different heavy metals will produce combined effect and form complex pollution. Studies have shown that there is a complex interaction between coexisting heavy metal pollutants, which not only improves the solubility of pollutants, but also makes the toxicity of complex pollutants stronger and more complex, and is closer to the actual pollution. Most of the current adsorption materials are applied to the removal of single heavy metal ions, and the treatment effect of heavy metals in actual situation is not good. Therefore, it is of great significance to design and prepare adsorption materials with broad-spectrum adsorption performance to realize the rapid and efficient adsorption of multiple coexisting heavy metal ions for the treatment of heavy metal pollution in water. At present, the main method of preparing broad-spectrum adsorption materials is to introduce functional groups on the surface of the material which can complex with multiple heavy metal ions, such as EDTA (Nature Communications, 2018, 9: 187, CN202210626830.X) and the like. In recent years, mussel-inspired technology can form a hydrophilic coating on the surface of various materials, which has the characteristics of mild reaction conditions and simple operation, and has attracted much attention in the field of heavy metal adsorption materials. However, the preparation time of mussel-inspired materials is long, and the material surface mainly contains hydroxyl groups, amino groups and other groups, which is difficult to meet the demand of adsorption and removal of coexisting heavy metal ions.

[0005] This invention addresses the issues of time-consuming and limited surface functional groups in mussel-inspired biomimetic technology. It proposes using oxidants to accelerate the oxidation of catechol derivatives, employing polyamine coupling to enhance the speed and efficiency of surface functionalization, and introducing thiol groups into the coating. By leveraging the synergistic effect among various adsorption functional groups, the adsorption performance of the material for coexisting heavy metal ions is improved. This invention solves the problem of time-consuming mussel-inspired biomimetic technology and provides more adsorption active groups, opening up new avenues for the adsorption of coexisting heavy metal ions. Summary of the Invention

[0006] This invention addresses the shortcomings of current broad-spectrum adsorption materials for heavy metals by proposing a method to introduce thiol groups into a mussel-inspired coating. By utilizing multiple adsorption functional groups, the adsorption performance of coexisting heavy metal ions is improved, and thiol-functionalized nonwoven fabrics are prepared, achieving efficient adsorption of heavy metals.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] This invention selects catechol and its derivatives as precursors to overcome the problem of high dopamine prices; it proposes to use oxidants to accelerate the oxidation rate of precursors and polyamine coupling reactions to improve the polymerization rate, which greatly shortens the preparation process of mussel biomimetic adsorbent materials; during the deposition process, sulfur-containing coupling agents are added and combined with reduction reactions to introduce thiol groups into the adsorbent material. By utilizing the synergistic effect of thiol groups and various groups in the mussel biomimetic coating, the adsorption performance of the adsorbent material for different heavy metal ions is improved.

[0009] A method for rapidly adsorbing heavy metal ions using thiol-functionalized nonwoven fabric includes the following steps:

[0010] a. Preparation of thiol-functionalized nonwoven fabrics

[0011] (1) Sonicate the non-woven fabric in an ethanol solution for 1 hour and then soak it in deionized water to wash it clean and remove surface contaminants;

[0012] (2) Add catechol and its derivatives, oxidant and polyamine to a 20% to 50% (V / V) ethanol aqueous solution at a certain molar ratio, adjust the pH value to 7-9, add sulfur-containing coupling agent, then add the above non-woven fabric, react for 10 to 40 minutes, add crosslinking agent, heat to 70℃ and react for 0.5 to 2 hours, wash, dry and set aside.

[0013] (3) The nonwoven fabric obtained in step (2) is stirred and reduced in a 0.5M reducing agent for 0.5 to 2 hours, then taken out, washed, and dried to obtain thiol functionalized fiber nonwoven fabric.

[0014] b. Application of rapid adsorption of heavy metal ions in water

[0015] A certain amount of thiol functionalized non-woven fabric is placed in an aqueous solution of heavy metal ions, the pH value of the solution is adjusted, and stirring adsorption is performed.

[0016] The present application has the following advantages:

[0017] 1) The use of oxidizing agents and polyamine coupling agents accelerates the mussel-inspired reaction and deposition rate, significantly accelerating the preparation process of the adsorption material.

[0018] 2) The introduction of thiol groups in the mussel-inspired coating improves the adsorption performance of the material for heavy metal ions by utilizing the synergistic effect of thiol groups and hydroxyl, amino and other adsorption functional groups in the mussel-inspired coating.

[0019] 3) The method has mild reaction conditions, simple operation, short time consumption and low cost, and can be used for industrial production and application. DETAILED DESCRIPTION

[0020] The following examples will further illustrate the present application, but not limit the present application.

[0021] Example 1

[0022] A. Preparation of thiol functionalized polypropylene non-woven fabric

[0023] 0.8809 g of catechol was dissolved in a mixed aqueous solution of 20 mL of ethanol and 20 mL of deionized water, 1.8256 g of ammonium persulfate and 0.5348 mL of ethylenediamine were added under stirring to prepare a reaction solution, the pH value was adjusted to 7.5, and then 671 μL of ethanedithiol was added. Stirring was performed at room temperature for 30 min, and 170 mL of deionized water was added. Then 2 g of polypropylene non-woven fabric treated with ethanol was added to the above reaction solution. Stirring was performed at room temperature for 30 min, 0.7535 mL of glutaraldehyde was added, and the temperature was raised to 70°C for reaction for 2 h. The above prepared non-woven fabric was taken out, washed, placed in 100 mL of 1.85 g / L sodium borohydride solution, and stirred for 1 h. After modification, it was washed with water and dried at 70°C to obtain the thiol modified non-woven fabric.

[0024] B. Study on the adsorption behavior of heavy metal ions

[0025] 10 ppm of Pb, Cu, Cd, Ni, Co and Zn heavy metal ion solutions were prepared respectively, the pH was adjusted to 6, 50 mg of thiol functionalized non-woven fabric was added, and the adsorption of heavy metal ions was performed in a water bath shaker at 150 r / min and 298 K. The removal rates of thiol functionalized non-woven fabric for Pb, Cu and Cd in water were close to 95%, and the removal rates for Ni, Co and Zn were close to 93%.

[0026] Example 2

[0027] A. Preparation of thiol-functionalized polypropylene nonwoven fabric

[0028] 1.2254 g of dopamine was dissolved in a mixed aqueous solution of 20 mL ethanol and 40 mL deionized water. Under stirring, 1.84 g of potassium periodate and 1.7194 mL of diethylenetriamine were added to prepare a reaction solution. The pH was adjusted to 7, and then 671 μL of ethylenedithiol was added. The reaction was stirred at room temperature for 30 min, and then 150 mL of deionized water was added. Subsequently, 1.5 g of ethanol-treated polypropylene nonwoven fabric was added to the above reaction solution. The reaction was stirred at room temperature for 30 min, and then 1.3935 g of ethylene glycol diglycidyl ether was added. The temperature was raised to 70 °C and the reaction was carried out for 1.5 h. The resulting nonwoven fabric was removed, washed, and placed in 100 mL of 4.5 g / L oxalic acid solution and stirred for 1 h. After modification, the fabric was washed with water and dried at 70 °C to obtain the mercapto-modified nonwoven fabric.

[0029] B. Study on the adsorption behavior of heavy metal ions

[0030] Solutions of heavy metal ions with a concentration of 20 ppm for Pb, Cu, Cd, Ni, Co, and Zn were prepared, and the pH was adjusted to 7. 30 mg of thiol-functionalized nonwoven fabric was added, and the heavy metal ion adsorption was carried out in a water bath shaker at 150 r / min and 298 K. The removal rates of Pb, Cu, and Cd in water by the thiol-functionalized nonwoven fabric were close to 93%, the removal rates of Ni and Co were close to 90%, and the removal rate of Zn was close to 88%.

[0031] Example 3

[0032] A. Preparation of thiol-functionalized polyethylene nonwoven fabric

[0033] 1.4413 g of caffeic acid was dissolved in a mixed aqueous solution of 30 mL ethanol and 40 mL deionized water. Under stirring, 3.4223 g of sodium periodate and 2.3826 mL of triethylenetetramine were added to prepare a reaction solution. The pH was adjusted to 8, and then 671 μL of ethylenedithiol was added. The reaction was stirred at room temperature for 30 min, and then 150 mL of deionized water was added. Subsequently, 2 g of ethanol-treated polyethylene nonwoven fabric was added to the above reaction solution. The reaction was stirred at room temperature for 30 min, and then 1.1333 mL of divinylbenzene was added. The temperature was raised to 70 °C and the reaction was carried out for 2 h. The resulting nonwoven fabric was removed, washed, and placed in 100 mL of 1.85 g / L sodium borohydride solution and stirred for 1 h. After modification, the fabric was washed with water and dried at 70 °C to obtain the mercapto-modified nonwoven fabric.

[0034] B. Study on the adsorption behavior of heavy metal ions

[0035] Preparation of the thiol-functionalized polyester nonwoven fabric A. Preparation of the thiol-functionalized polyester nonwoven fabric

[0036] Example 4

[0037] A. Preparation of the thiol-functionalized polyester nonwoven fabric

[0038] A. Preparation of the thiol-functionalized polyester nonwoven fabric

[0039] B. Adsorption behavior of heavy metal ions

[0040] A. Preparation of the thiol-functionalized polyester nonwoven fabric

[0041] Example 5

[0042] A. Preparation of the thiol-functionalized polyester nonwoven fabric

[0043] A solution of 0.8809 g catechol was prepared by dissolving it in a mixture of 30 mL ethanol and 30 mL deionized water, and then 1.84 g sodium periodate and 1.1913 mL triethylenetetramine were added under stirring to prepare a reaction solution, and the pH value was adjusted to 7.5, and then 336 μL ethanedithiol was added. The reaction was stirred at room temperature for 30 min, and then 170 mL deionized water was added. Then 1.5 g of polyethylene non-woven fabric treated with ethanol was added to the above reaction solution. The reaction was stirred at room temperature for 30 min, and then an appropriate amount of polyethylene glycol was added, and the temperature was raised to 70°C for 2 h. The non-woven fabric prepared above was taken out, washed, and placed in 100 mL of a 1.85 g / L sodium borohydride solution and stirred for 1 h. After the modification was completed, it was washed with water and dried at 70°C to obtain a thiol-modified non-woven fabric.

[0044] B. Study on the adsorption behavior of heavy metal ions

[0045] Solutions of Pb, Cu, Cd, Ni, Co and Zn heavy metal ions with a concentration of 100 ppm were prepared respectively, and the pH was adjusted to 6. 50 mg of thiol-functionalized non-woven fabric was added, and the adsorption of heavy metal ions was carried out in a water bath shaker at 150 r / min and 298 K. The removal rates of Pb, Cu and Cd in water by the thiol-functionalized non-woven fabric were all close to 85%, the removal rates of Ni and Co were all close to 83%, and the removal rate of Zn was close to 80%.

[0046] Example 6

[0047] A. Preparation of thiol-functionalized polyester non-woven fabric

[0048] A solution of 1.352 g 3,4-dihydroxyphenylacetic acid was prepared by dissolving it in a mixture of 10 mL ethanol and 40 mL deionized water, and then 3.6512 g ammonium persulfate and 1.0696 mL ethylenediamine were added under stirring to prepare a reaction solution, and the pH value was adjusted to 7, and then 336 μL ethanedithiol was added. The reaction was stirred at room temperature for 30 min, and then 170 mL deionized water was added. Then 2 g of polyester non-woven fabric treated with ethanol was added to the above reaction solution. The reaction was stirred at room temperature for 30 min, and then 1.5069 mL glutaraldehyde was added, and the temperature was raised to 70°C for 1.5 h. The non-woven fabric prepared above was taken out, washed, and placed in 100 mL of a 4.5 g / L oxalic acid solution and stirred for 1 h. After the modification was completed, it was washed with water and dried at 70°C to obtain a thiol-modified non-woven fabric.

[0049] B. Study on the adsorption behavior of heavy metal ions

[0050] Preparation of Pb / Cu / Cd ternary heavy metal ion solution with concentration of 10 ppm, adjust pH to 6, add 30 mg of thiol functionalized non-woven fabric, carry out heavy metal ion adsorption in water bath shaker at 150 r / min and 298 K, the removal rate of Pb in Pb / Cu / Cd ternary system is close to 95%, and the removal rates of Cu and Cd are both close to 93%; the removal rates of Ni and Co in Ni / Co / Zn ternary system are both close to 93%, and the removal of Zn is close to 86%.

[0051] Example 7

[0052] A. Preparation of thiol functionalized polypropylene non-woven fabric

[0053] Dissolve 1.4413 g of caffeic acid in a mixed aqueous solution of 30 mL of ethanol and 40 mL of deionized water, add 3.4223 g of sodium periodate and 2.3826 mL of triethylenetetramine under stirring conditions to prepare a reaction solution, adjust the pH value to 8.5, and then add 671 μL of ethanedithiol. Stir at room temperature for 30 min, and then add 150 mL of deionized water. Then add 2 g of polypropylene non-woven fabric treated with ethanol into the above reaction solution. Stir at room temperature for 30 min, add 1.1333 mL of divinylbenzene, and heat to 70°C for 2 h. Take out the prepared non-woven fabric, wash it, and place it in 100 mL of 1.85 g / L sodium borohydride solution and stir for 1 h. After modification, wash with water and dry at 70°C to obtain the thiol modified non-woven fabric.

[0054] B. Study on the adsorption behavior of heavy metal ions

[0055] Preparation of Pb, Cu, Cd, Ni, Co and Zn heavy metal ion solutions with concentration of 10 ppm respectively, adjust pH to 8, add 50 mg of thiol functionalized non-woven fabric, carry out heavy metal ion adsorption in water bath shaker at 150 r / min and 308 K, the removal rates of Pb, Cu and Cd in water are all close to 93%, the removal rate of Ni is close to 89%, and the removal rates of Co and Zn are both close to 85%.

[0056] Example 8

[0057] A. Preparation of thiol functionalized polyester non-woven fabric

[0058] 0.8809 g catechol was dissolved in 20 mL of a mixed aqueous solution of ethanol and deionized water, 1.5 mL of hydrogen peroxide, 2.3826 mL of triethylenetetramine were added under stirring to prepare a reaction solution, the pH value was adjusted to 7.5, and then 671 μL of ethanedithiol was added. The reaction was stirred at room temperature for 30 min, and then 150 mL of deionized water was added. Subsequently, 2 g of polyester non-woven fabric treated with ethanol was added to the above reaction solution. The reaction was stirred at room temperature for 30 min, and then 1.3935 g of ethyleneglycol diglycidyl ether was added. The temperature was raised to 70°C, and the reaction was carried out for 1.5 h. The non-woven fabric prepared above was taken out, washed, and placed in 100 mL of a 1.85 g / L sodium borohydride solution, and stirred for 1 h. After the modification was completed, the product was washed with water and dried at 70°C to obtain a thiol-modified non-woven fabric.

[0059] B. Adsorption behavior of heavy metal ions

[0060] Pb / Cu / Cd / Ni, Pb / Cu / Co / Zn quaternary heavy metal ion solutions with a concentration of 10 ppm were prepared respectively, the pH was adjusted to 6, 50 mg of thiol-functionalized non-woven fabric was added, and the adsorption of heavy metal ions was carried out in a water bath shaker at 150 r / min and 298 K. The removal rates of Pb and Cu in the Pb / Cu / Cd / Ni quaternary system were both close to 93%, and the removal rates of Cd and Ni were both close to 88%. The removal rates of Pb and Cu in the Pb / Cu / Co / Zn quaternary system were both close to 92%, the removal rate of Ni was close to 88%, and the removal rate of Zn was close to 83%.

Claims

1. A method for rapid adsorption of heavy metal ions by mercapto-functionalized nonwoven fabric, characterized by, The application relates to a preparation method of a mercapto-functionalized non-woven fabric and rapid adsorption of heavy metal ions, and particularly relates to the following steps. A. Preparation of the mercapto-functionalized non-woven fabric (1) ultrasonic treatment of the non-woven fabric in an ethanol solution for 1 h and immersion washing with deionized water to remove surface contaminants; (2) adding catechol and its derivatives, an oxidizing agent, a coupling agent and a sulfur-containing coupling agent into a 20%-50% (V / V) ethanol aqueous solution according to a certain molar ratio, adjusting the pH value to 7-9, adding the non-woven fabric, reacting for 10-40 min, adding a crosslinking agent, and reacting at 70 DEG C for 0.5-2 h, washing, drying, and preparing; (3) stirring and reducing the non-woven fabric prepared in step (2) in a 0.5M reducing agent for 0.5-2 h, taking out, washing, and drying to obtain the mercapto-functionalized non-woven fabric; B. Rapid adsorption of heavy metal ions in water a certain amount of the mercapto-functionalized non-woven fabric is placed in a heavy metal ion aqueous solution, the pH value of the solution is adjusted, and stirring adsorption is carried out.

2. The method of claim 1, wherein: The non-woven fabric in step a is one of polypropylene, polyethylene, polyester and nylon.

3. The method of claim 1, wherein: The catechol derivative in step a is one or more of catechol, dopamine, caffeic acid and 3,4-dihydroxybenzoic acid.

4. The method of claim 1, wherein: The oxidizing agent in step a is one of sodium periodate, ammonium persulfate, potassium persulfate and hydrogen peroxide.

5. The method of claim 1, wherein: The coupling agent in step a is one of ethylenediamine, triethylenetetramine and tetraethylenepentamine.

6. The method of claim 1, wherein: The reagent containing a mercapto functional group in step a is one of ethanedithiol, mercaptoethanol and ethanethiol.

7. The method of claim 1, wherein: The crosslinking agent in step a is one of divinylbenzene, styrene, glutaraldehyde, ethylene glycol diglycidyl ether and polyethylene glycol.

8. The method of claim 1, wherein: The reducing agent in step a is one of lithium aluminum hydride, oxalic acid and sodium borohydride.

9. The method of claim 1, wherein: The heavy metal in step b is one or more of Pb, Cu, Cd, Ni, Co and Zn.