A large-flux reinforced hollow fiber membrane and its preparation method

Abstract

The invention relates to a large-flux reinforced hollow fiber membrane, wherein the separation membrane layer is composed of the following components in parts by weight: 22-30 parts of polyvinylidene fluoride, 10-20 parts of hydrophilic agent, 50-50 parts of polar solvent 60 parts, 10-20 parts of porogen, 5-10 parts of auxiliary agent, and the hydrophilic agent contains triethanolamine. The present invention adopts hydrophilic agent, auxiliary agent and polyvinylidene fluoride to blend and modify under polar solvent to reduce the surface tension of the membrane surface and the inner wall of the membrane hole, improve the hydrophilicity of polyvinylidene fluoride, and the hydrophilic agent The triethanolamine can generate hydrogen bonds with the polar bonds in the additives, so that it can maintain the hydrophilicity for a long time, improve the anti-fouling performance of the hollow fiber membrane, and maintain a high operating flux for a long time. The triethanolamine can also be adsorbed on the surface of the hollow fiber material by the hydrogen bond force, thereby enhancing the adhesion strength between the separation membrane layer and the hollow fiber, and adding the hollow fiber as a support can prevent the membrane material from breaking.

Description

technical field [0001] The invention relates to the technical field of ultrafiltration membranes, in particular to a large flux reinforced hollow fiber membrane and a preparation method thereof. Background technique [0002] Ultrafiltration is a membrane separation process that takes pressure difference as the driving force and uses the sieving mechanism to intercept macromolecular solutes and separate them from solvents or small molecular solutes according to the size of the substance. The effective pore size of the ultrafiltration membrane used is between 2 ~100nm. Utilizing the screening effect of the micropores on the surface of the ultrafiltration membrane, the separation and purification of substances with different molecular weights can be realized, and it has a good effect on the removal of particles, colloids, bacteria and various organic substances. In recent years, it has been widely used in water treatment, food, Electronics, machinery, chemical industry, petrol...

AI Technical Summary

Problems solved by technology

[0004] The hollow fiber membranes in the prior art have some defects: 1. The unsupported polyvinylidene fluoride hollow fiber membrane has a thick skin layer, which is prone to broken wires and low processing efficiency; 2. The inner lining enhances the bonding strength of the hollow fiber membrane separation layer Low, the shedding of the cortex affects the treatment effect and service life; 3. The polyvinylidene fluoride hollow fiber membrane has poor hydrophilicity, and it is easy to absorb pollutants during use, reducing the treatment efficiency and other defects

The bond strength and surface hydrophilicity of the separation layer are two important factors affecting the separation performance of the lining-reinforced hollow fiber membrane. It can be seen that the performance of the hollow fiber membrane in the prior art needs to be further improved