Visible-light photocatalyzed flat plate type ultrafiltration membrane based on metal doped nTiO2 and preparation method

Abstract

The invention discloses a visible-light photocatalyzed flat plate type ultrafiltration membrane based on metal doped nTiO2 and a preparation method and belongs to the technical field of membrane separation. The preparation method comprises the following steps: adding 8.0%-20.0% (w / w) of polysulfone / polyethersulfone, 5.0%-15.0% (w / w) of a pore forming agent, 0.05%-2.0% (w / w) of a surfactant, 0.05%-5.0% (w / w) of the metal doped nTiO2 and 58.0%-86.9% (w / w) of a solvent into a three-opening round bottomed flask according to a certain sequence; stirring at 30 DEG C to 80 DEG C and dissolving for 5hr to 16hr until the materials are completely dissolved; standing and de-foaming for 8hr to 24hr to prepare a film casting solution; and forming a film on a clean glass plate by adopting a phase inversion method to prepare the visible-light photocatalyzed flat plate type ultrafiltration membrane. The pure water flux of the prepared ultrafiltration membrane is more than or equal to 430L / m<2>.hr.0.1MPa, the retention rate of bovine serum albumin is more than or equal to 90.00% and the degradation removing rate of fulvic acid is more than or equal to about 60% (when the ultrafiltration membrane is operated for 1h under simulated visible light; and the visible-light photocatalyzed flat plate type ultrafiltration membrane has good anti-pollution and visible-light photocatalysis performances. The product is particularly suitable for slightly-polluted water source water treatment, seawater desalination pre-treatment and treatment and recycling of wastewater in the fields of biology, chemical industry, medicines and the like.

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 flat ultrafiltration membrane and preparation method thereof. Background technique [0002] The scarcity of water resources and the increasingly serious water pollution have become the bottlenecks restricting social progress and economic development. Since Shanghai is extremely rich in water resources and produces a large amount of waste water, sewage recycling and seawater desalination have become a strategic choice to solve the water crisis. Membrane separation technology is one of the best choices among many technologies for wastewater recycling. [0003] Mixed matrix membrane, also known as hybrid membrane, is a membrane formed by chemically cross-linking or micro-mixing organic and inorganic components, also known as "organic-inorganic hybrid membrane", because it has the corrosi...

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 Improving the visible light catalytic properties of polymer ultrafiltration membranes and preparing planar mixed-matrix ultrafiltration membranes with visible light catalytic activity can significantly improve the photocatalytic properties of polymer ultrafiltration membranes. There are no relevant literature reports at home and abroad.