Glycosyl-modified reverse osmosis composite membrane and preparation method thereof

Abstract

The invention relates to a preparation method of a glycosyl modified reverse osmosis composite membrane. The method comprises the following steps that inorganic nanoparticles are subjected to oiling treatment; the treated nanoparticles are blended with FEP (fluorinated ethylene propylene) copolymer fluororesin powder and an additive in a high-speed material blender; a mixture is pressed into a FEP fluoroplastic flat sheet membrane at high temperature by a hot press; the FEP fluoroplastic flat sheet membrane is subjected to extraction and alkali washing to form a micro-nano FEP reverse osmosis membrane support layer; the support layer is irradiated in plasmas, so that a hydrophilic polyacrylic acid microlayer is grafted at the surface of the support layer; the support layer is soaked in an aqueous phase solution; after the support layer is taken out, excessive aqueous phase solution on the surface is removed; then, the support layer is soaked in a polyfunctional group acyl chloride oil phase mixed solution; after the support layer is taken out, excessive oil phase solution on the surface is removed; a membrane sheet is formed and is dried; the dried membrane sheet is irradiated by atmospheric-pressure plasmas, so that the glycosyl polymerization is sufficient; after the membrane sheet is rinsed in pure water, the glycosyl modified reverse osmosis composite membrane is obtained. The product intensity is high; the flux is great; the acid and alkali resistance is realized; the permanent hydrophilic performance is realized.

Description

technical field [0001] The invention relates to a glycosyl-modified reverse osmosis composite membrane and a preparation method thereof. Background technique [0002] Reverse osmosis membrane is the core component to realize reverse osmosis, and it is an artificial semipermeable membrane with certain desalination characteristics. Generally made of polymer materials. Such as cellulose acetate film, aromatic polyhydrazide film, aromatic polyamide film. The diameter of surface micropores is generally between 0.5 and 10 nm. The reverse osmosis membrane should have the following characteristics: (1) It should have a high desalination rate at a high flow rate; (2) It has high mechanical strength and service life; (3) It can function at a low operating pressure; (4) It can Resistant to the influence of chemical or biochemical effects; (5) less affected by factors such as pH value and temperature; (6) easy source of raw materials for film making, easy processing and low cost. A ...

AI Technical Summary

Problems solved by technology

However, the polysulfone support membrane has strong hydrophobicity, is very sensitive to organic solvents, and is not resistant to chlorine, which limits its application in reverse osmosis membranes in special fields.

[0006] 2. In terms of the separation layer, due to the hydrophobicity of the membrane, the membrane is easily polluted. Particles, colloids or solute molecules in the feed water are adsorbed and precipitated on the surface or inside the membrane, resulting in a sharp drop in flux and poor water quality. Reduce the service life of the membrane and increase the operating cost

In addition, the support layer and separation layer are also easy to interact with oxidants and be oxidized, which directly leads to membrane performance failure and seriously affects the service life of the membrane.

[0007] 3. Due to the poor hydrophilicity of the reverse osmosis membrane, the reverse osmosis water flux is generally relatively low, which increases the cost of engineering manufacturing and limits the application of reverse osmosis membranes in large-scale seawater desalination, tap water purification, sewage reuse and other fields