Visible photocatalytic flat plate type ultrafiltration membrane based on Ag/AgX and preparation method

Abstract

The invention discloses a visible photocatalytic flat plate type ultrafiltration membrane based on Ag / AgX and a preparation method and belongs to the technical field of membrane separation. 8.0%-20.0% (w / w) of polysulfone or polyether sulfone, 5.0%-15.0% (w / w) of pore-foaming agent, 0.05%-2.0% (w / w) of surface active agent, 0.05%-5.0% (w / w) of Ag / AgX and 58.0%-86.9% (w / w) of solvent are added to a three-opening round-bottom flask according to a certain sequence, stirring dissolution is performed at the temperature of 30-80 DEG C for 5-16 hours till the components are completely dissolved, and standing and defoaming are performed for 8-24 hours to prepare membrane casting liquid; a phase inversion method is adopted to scrape a membrane on a clean glass plate to prepare the visible photocatalytic flat plate type ultrafiltration membrane. The pure water flux of the prepared ultrafiltration membrane is greater than or equal to 500 L / m<2>.hr.0.1 MPa, the bovine serum albumin retention rate is 90.00% or above, the fulvic acid degradation removal rate is 70% or above (operation is performed for 1 hour under simulated visible light), and the membrane has good contamination resistance and visible light catalysis properties. The visible photocatalytic flat plate type ultrafiltration membrane is especially applicable to water treatment of micro-polluted water sources, seawater desalination pretreatment, treatment and recycling of wastewater in the biological, chemical and pharmaceutical fields 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 an Ag / AgX-based visible light catalyzed flat-plate ultrafiltration membrane and a 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 crosslinking...

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Problems solved by technology

[0004] 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 considered that the separation membrane showed good photocatalytic degradation performance and anti-protein pollution 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

[0006] The present invention uses Ag / AgX to improve the visible light catalytic properties of polymer ultrafiltration membranes, and prepares flat-plate mixed matrix ultrafiltration membranes with visible light catalytic activity. There are no relevant literature reports at home and abroad.