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CN-121715064-B - Quercetin doped reverse osmosis composite membrane, preparation method thereof and water purification method

CN121715064BCN 121715064 BCN121715064 BCN 121715064BCN-121715064-B

Abstract

The invention belongs to the technical field of membrane separation, and particularly relates to a quercetin doped reverse osmosis composite membrane, a preparation method thereof and a water purification method. The quercetin doped reverse osmosis composite membrane comprises a polysulfone microfiltration base membrane and a quercetin doped polyamide selective layer, wherein the quercetin doped polyamide selective layer is attached to at least one side surface of the polysulfone microfiltration base membrane, and comprises quercetin and a polyamide skeleton, and the quercetin and the polyamide skeleton are connected through ester bonds and/or hydrogen bonds. The quercetin doped reverse osmosis composite membrane at least meets one of the following conditions of surface roughness of 121-199nm, water contact angle of 50-60 degrees, retention rate of 2000 mg.L ‑1 NaCl solution of more than or equal to 95% at 25 ℃ plus or minus 1 ℃, zeta potential of-30 mV to-60 mV at pH value=7, quercetin slow release rate of 0.1 mug.cm ‑2 ·d ‑1 ~10μg·cm ‑2 ·d ‑1 , killing rate of colibacillus of more than or equal to 90%, and killing rate of staphylococcus aureus of more than or equal to 90%.

Inventors

  • ZHAO DIELING
  • LIU YIFAN
  • YUAN SHASHA
  • LIN HONGJUN

Assignees

  • 浙江师范大学

Dates

Publication Date
20260512
Application Date
20260224

Claims (8)

  1. 1. A quercetin-doped reverse osmosis composite membrane is characterized by comprising a polysulfone microfiltration base membrane and a quercetin-doped polyamide selection layer; the quercetin doped polyamide selective layer is attached to at least one side surface of the polysulfone microfiltration base membrane; the quercetin-doped polyamide selection layer comprises quercetin and a polyamide skeleton, wherein the quercetin and the polyamide skeleton are connected through ester bonds and/or hydrogen bonds; The quercetin doped polyamide selective layer is a crosslinked network formed by an interfacial polymerization reaction of m-phenylenediamine, 1,3, 5-trimesic acid chloride and quercetin, and the thickness of the quercetin doped polyamide selective layer is 80-150 nm; The quercetin slow release rate of the quercetin doped reverse osmosis composite membrane is 0.1 mug cm -2 ·d -1 ~10μg·cm -2 ·d -1 .
  2. 2. The quercetin doped reverse osmosis composite membrane according to claim 1, wherein the quercetin doped reverse osmosis composite membrane fulfils at least one of the following conditions: The surface roughness is 121 nm-199nm; the water contact angle is 50-60 degrees; The retention rate of 2000 mg.L -1 NaCl solution is more than or equal to 95% under the conditions of 20bar and 25 ℃ plus or minus 1 ℃; The Zeta potential is-30 mV to-60 mV when the pH value is=7; the killing rate of the escherichia coli is more than or equal to 90 percent; the killing rate of staphylococcus aureus is more than or equal to 90 percent.
  3. 3. A method for preparing a quercetin-doped reverse osmosis composite membrane according to any one of claims 1-2, comprising the steps of: Immersing the pretreated polysulfone microfiltration base membrane in an aqueous phase quercetin solution, and taking out to obtain an aqueous phase loaded polysulfone microfiltration base membrane, wherein the aqueous phase quercetin solution comprises 0.01wt% -0.10wt% of quercetin, 0.04wt% of sodium hydroxide, 2wt% of m-phenylenediamine, 0.15wt% of sodium dodecyl sulfate and 0.05wt% of 4-dimethylaminopyridine based on the total mass of the aqueous phase quercetin solution; Immersing the aqueous phase loaded polysulfone microfiltration base membrane in a1, 3, 5-trimesoyl chloride/n-hexane solution, and performing interfacial polymerization reaction to form a quercetin-doped polyamide selection layer; and (5) post-treating to obtain the quercetin doped reverse osmosis composite membrane.
  4. 4. The preparation method according to claim 3, wherein the mass fraction of quercetin in the aqueous-phase quercetin solution is 0.02% -0.06%.
  5. 5. The method of preparing a water-phase quercetin solution according to claim 3, wherein the method comprises adding quercetin into a sodium hydroxide solution, dispersing to obtain an activated quercetin solution, and sequentially adding metaphenylene diamine, sodium dodecyl sulfate and 4-dimethylaminopyridine into the activated quercetin solution to obtain a water-phase quercetin solution.
  6. 6. The preparation method according to claim 3, wherein the mass fraction of 1,3, 5-trimesoyl chloride in the 1,3, 5-trimesoyl chloride/n-hexane solution is 0.12-0.18 wt%.
  7. 7. A process according to claim 3, wherein the interfacial polymerization reaction is controlled to be carried out at 5℃to 10℃and/or The post-treatment condition is that the material is dried for 0.5 min-5 min in normal hexane or air atmosphere, and cured for 3 min-10 min at 40-80 ℃.
  8. 8. A water purification method, characterized in that the quercetin-doped reverse osmosis composite membrane according to any one of claims 1 to 2 or the quercetin-doped reverse osmosis composite membrane prepared by the preparation method of any one of claims 3 to 7 is used for water purification.

Description

Quercetin doped reverse osmosis composite membrane, preparation method thereof and water purification method Technical Field The invention belongs to the technical field of membrane separation, and particularly relates to a quercetin doped reverse osmosis composite membrane, a preparation method thereof and a water purification method. Background The Reverse Osmosis (RO) membrane is widely applied to the fields of sea water desalination, sewage treatment, drinking water purification and the like, but has a plurality of defects in the long-term operation process, namely, the membrane has insufficient surface hydrophilicity, is easy to cause adhesion of pollutants, such as organic matters, bacteria and the like to cause membrane pollution, reduces the operation flux and the service life of the membrane, increases the operation cost, has single surface charge property, has weaker electrostatic repulsive interaction on the negatively charged bacteria, dissolved organic matters and the like, further aggravates the pollution problem, and has no antibacterial function, the bacteria bred on the surface of the membrane not only can block membrane pore channels, but also can possibly generate toxic metabolites to influence the water quality in the long-term operation process, and fourth, the existing membrane material has a lack of response release function, can not realize controllable release of functional matters through external stimulus (such as enzyme existence condition), and is difficult to meet the dynamic antibacterial requirement under the complex water treatment scene. Disclosure of Invention The invention aims to provide a quercetin-doped reverse osmosis composite membrane, a preparation method thereof and a water body purifying method. According to the invention, natural flavonoid polyphenol quercetin is introduced in the interfacial polymerization step, so that the natural flavonoid polyphenol quercetin is stably combined in the polyamide selection layer in various modes such as ester bond, hydrogen bond and van der Waals effect, and esterase in the microenvironment of the surface of the coating can be gradually hydrolyzed in the biological polluted environment, so that the controlled-release antibacterial effect is realized as required. The invention utilizes the quercetin polyhydroxy structure to improve the hydrophilicity, the electrical property and the interface energy of the membrane surface, and realizes the synergistic anti-fouling effect of 'structure optimization + slow release antibacterial', thereby obviously improving the long-term anti-fouling capability of the reverse osmosis composite membrane in the treatment of seawater, brackish water and high-salt wastewater. The first aspect of the invention provides a quercetin-doped reverse osmosis composite membrane, which comprises a polysulfone microfiltration base membrane and a quercetin-doped polyamide selective layer, wherein the quercetin-doped polyamide selective layer is attached to at least one side surface of the polysulfone microfiltration base membrane, and comprises quercetin and a polyamide skeleton, and the quercetin and the polyamide skeleton are connected through an ester bond and/or a hydrogen bond. The reverse osmosis composite membrane is stably combined with a polyamide skeleton through quercetin, so that the membrane has antibacterial and hydrophilic properties, and meanwhile, the separation function of the reverse osmosis composite membrane is considered. In some embodiments of the invention, the quercetin doped polyamide selection layer has a thickness of 50nm to 300nm, preferably 80nm to 150nm. The thickness of the selective layer is adapted to the reverse osmosis separation requirement, and both high retention rate and excellent water flux are achieved. In some embodiments of the invention, the quercetin-doped polyamide selection layer is a crosslinked network formed by interfacial polymerization of metaphenylene diamine, 1,3, 5-trimesoyl chloride, and quercetin. The polyamide selective layer doped with the quercetin is a crosslinked network formed by interfacial polymerization, so that the compactness and stability of the structure of the selective layer are improved, and the uniform dispersion and difficult loss of the quercetin are facilitated. In some embodiments of the invention, the quercetin-doped reverse osmosis composite membrane at least meets one of the following conditions of surface roughness of 121-199nm, water contact angle of 50-60 degrees, retention rate of 2000 mg.L -1 NaCl solution of 95% or more at 20bar and 25 ℃ plus or minus 1 ℃, zeta potential of-30 mV-60 mV at pH value=7, quercetin slow release rate of 0.1 mug.cm -2·d-1~10μg·cm-2·d-1, E.coli killing rate of 90% or more, and staphylococcus aureus killing rate of 90% or more. The conditions enable the reverse osmosis composite membrane to have good pollution resistance (low roughness and moderate water contact angle), high separation performance (