Hollow polyethersulfone fiber ultrafiltration membrane capable of resisting biological pollution and preparation method of membrane

Abstract

The invention relates to a preparation method of a hollow polyethersulfone fiber ultrafiltration membrane capable of resisting biological pollution. The preparation method comprises the following steps: uniformly dispersing a modified material which is titanium dioxide / chitosan / graphene composite material in an organic solvent through ultrasounds, then adding a polyethersulfone material and an additive, adjusting the temperature of a membrane casting solution, uniformly stirring the solution and then standing the solution to obtain the membrane casting solution; and preparing the hollow fiber ultrafiltration membrane by using a dry-wet phase transformation spinning method, and adjusting the structure and the performance of the ultrafiltration membrane by controlling parameters such as temperatures and composition of a external gel bath and a core solution, working power of a metering pump, flow of the core solution, dragging speed of a membrane filament and the like. The water transmission coefficient of the prepared ultrafiltration membrane filament is greater than 150L.m<-2>.h<-1> under the pressure of 0.1MPa; the interception rate of egg albumin (45000) is greater than or equal to 90%; the flux recovery rate of the ultrafiltration membrane is greater than or equal to 60%; the antibacterial rate of escherichia coli is greater than or equal to 70%; the antibacterial rate of staphylococcus aureus is greater than or equal to 72%; the mechanical resistance intensity is greater than or equal to 4.5MPa. The ultrafiltration membrane prepared by adopting the preparation method is good in capability of resisting biological pollution and mechanical resistance and especially applicable to the fields of desalination pretreatment of seawater, brackish water, biochemical industry, pharmaceuticals and foods.

Description

technical field [0001] The invention relates to a preparation method of a hollow fiber membrane, in particular to a preparation method of an anti-biological pollution ultrafiltration membrane applicable to seawater desalination pretreatment and MBR, and belongs to the technical field of ultrafiltration membrane blending modification. Background technique [0002] Polyethersulfone (PES) is a new type of high temperature resistant engineering material developed by ICI in 1972. It is a thermoplastic polymer material that is widely used at present. Because there is no aliphatic and ester structure in its molecular structure, it shows excellent thermal stability and oxidation resistance. Its glass transition temperature is 230°C, and its continuous use temperature can reach 180°C-200°C, and it can withstand 150°C. ℃-180℃ hot water or steam, the high temperature performance is comparable to that of polyimide, but the cost is much lower than the latter. Polyethersulfone molecule c...

AI Technical Summary

Problems solved by technology

[0003] Nano-titanium dioxide is a classic inorganic antibacterial material and photocatalytic material, which has long been applied to the field of antibacterial modification of membranes. Fujishima and Honda first discovered the phenomenon of photocatalytic water decomposition at the n-type semiconductor TiO2 electrode. At present, the most active research on TiO2 photocatalysis The field is in the photodegradation of organic matter. As a photocatalyst, TiO2 can decompose or mineralize organic matter, viruses, fungi, bacteria, algae, and cancer cells into non-toxic inorganic ions such as CO2 and H2O, but there is a photon energy utilization rate of TiO2 Less than 10%, the lifetime of electrons and holes generated by photoexcitation is very short (within 10-6 ~ 10-15 seconds), and it is easy to recombine to affect the photocatalytic activity

Chitosan (CS) is a natural antibacterial agent, which is non-toxic, good antibacterial, reproducible and biodegradable, but chitosan has the disadvantage of poor stability. This material has also been widely used in the resistance of membranes. Pollution modification