Visible-light-catalysis hollow fiber ultra-filtration membrane based on metal-doped nTiO2 and preparing method

Abstract

The invention discloses a visible-light-catalysis hollow fiber ultra-filtration membrane based on metal-doped nTiO2 and a preparing method, and belongs to the technical field of membrane separation. The preparing method includes the steps that 10.0%(w/w)-25.0%(w/w) of polysulfone or polyether sulfone, 8.0%(w/w)-17.0%(w/w) of a pore-foaming agent, 0.1%(w/w)-2.0%(w/w) of a surfactant, 0.1%(w/w)-5.0%(w/w) of the metal-doped nTiO2 and 51.0%(w/w)-81.8%(w/w) of a solvent are added into a dissolving tank in a certain sequence, the mixture is stirred and dissolved for 5 hours to 16 hours at the temperature of 35 DEG C to 95 DEG C till the mixture is completely dissolved, standing defoaming is carried out for 8 hours to 36 hours, and membrane casting liquid is prepared; the visible-light-catalysis hollow fiber ultra-filtration membrane is prepared with the traditional dry-wet spinning technology. The pure water flux of the ultra-filtration membrane prepared with the method is larger than or equal to 300 L/m<2>.hr.0.1MPa, the bovine-serum-albumin reject rate is larger than or equal to 90.00%, the degradation removing rate of fulvic acid is about 60% (under simulated visible light, running is carried out for 1 hour), and the good antifouling performance and the good visible-light-catalysis performance are achieved. The visible-light-catalysis hollow fiber ultra-filtration membrane is particularly suitable for micro-polluted-water-source water deep treatment, seawater desalinization pretreatment, deep treatment and recycling of wastewater in the field of biology chemical engineering and medicine.

Description

technical field [0001] The invention relates to a polymer mixed matrix ultrafiltration membrane and a preparation method thereof, in particular to a metal-doped nTiO 2 Visible light catalytic hollow fiber ultrafiltration membrane and preparation method thereof. Background technique [0002] The scarcity of water resources and increasingly serious water pollution have become bottlenecks restricting social progress and economic development. The development of new water sources and the utilization of waste water resources have also become issues of global concern. Due to the extremely rich water resources in Shanghai and the large amount of waste water generated, the recycling of sewage and seawater desalination have become strategic choices to solve the water resource crisis. Among many sewage resource technologies, membrane separation technology is one of the best choices. [0003] Mixed matrix membrane, also known as hybrid membrane, is a membrane formed by chemical crossl...

AI Technical Summary

Problems solved by technology

[0005] Chinese patent CN104383821A uses graphene oxide to support magnetic particles with a core-shell structure @TiO 2 The modified separation membrane was prepared, and it was believed that the separation membrane showed good photocatalytic degradation performance and protein pollution resistance performance for the target pollutant bovine serum albumin, but the separation performance and visible light catalytic degradation performance of the prepared membrane were not clarified in the patent application advantages and disadvantages, and the preparation process of the separation membrane is complicated; at the same time, the magnetic particles @TiO 2 The preparation method is complicated and the cost is high

Chinese patent CN102989329A passed AgNO 3 、TiO 2 Blending modification to prepare ultrafiltration membranes, in fact, mainly uses AgNO 3 Visible light catalytic activity, and the degradation rate is relatively slow (in the patent, the degradation rate of methylene blue is characterized by light for 10 hours), and it is impossible to prepare a separation membrane for separation and visible light catalysis at the same time; 3 PO 4 / TiO 2 Complex (Ag 3 PO 4 Nanoparticle deposition onto TiO 2 Surface) and polyvinylidene fluoride materials are blended and modified, so that the modified film has visible light catalytic antibacterial and antifouling properties, mainly using the deposited on TiO 2 Ag on the surface 3 PO 4 Particles degrade the organic matter adsorbed during the application of the separation membrane to reduce membrane fouling, and have not been used to prepare a separation membrane with both separation and visible light catalytic properties; at the same time, neither of these two patents has a synergistic effect to make full use of silver salts and TiO 2 The catalytic performance of silver salt or silver salt and TiO is only utilized by blending or deposition 2 Respective catalytic activity, visible light catalytic efficiency is low

The present invention adopts nTiO 2 doped with metal salts to give full play to metal salts and nTiO 2 The synergistic effect further enhances the nTiO 2 Visible light photocatalytic activity, and using metal doped nTiO 2 Improve the photocatalytic properties of polymer ultrafiltration membranes, prepare hollow fiber mixed matrix ultrafiltration membranes with visible light catalytic activity and realize industrialization. So far, no similar visible light catalytic hollow fiber ultrafiltration membrane products have been produced in China. Have not seen related literature reports