Metal-doped g-C3N4-based visible light catalysis hollow fiber ultrafiltration membrane and preparation method

Abstract

The invention discloses a metal-doped g-C3N4-based visible light catalysis hollow fiber ultrafiltration membrane and preparation method, belonging to the technical field of membrane separation. The preparation method comprises the following steps: adding the following components in percentage by weight: 10.0-25.0% of polysulfone or polyether sulfone, 8.0-17.0% of a pore-foaming agent, 0.1-2.0% of a surface active agent, 0.1-5.0% of metal-doped g-C3N4, and 51.0-81.8% of a solvent into a dissolving tank in a certain sequence, agitating and dissolving for 5-16 hours at the temperature of 35-95 DEG C until the complete dissolving is reached, standing and defoaming for 8-36 hours to obtain a membrane casting solution; and preparing the visible light catalysis hollow fiber ultrafiltration membrane by adopting the traditional dry-wet process spinning technology. The flux of pure water for preparing the ultrafiltration membrane is more than or equal to 330L / m<2>.hr.0.1MPa, the retention rate of bovine serum albumin is more than or equal to 90.00%, the removal rate for degrading fulvic acid is more than or equal to 65% (under the conditions of running for 1 hour and simulating visible light), the visible light catalysis hollow fiber ultrafiltration membrane has good anti-pollution performance and visible light catalysis performance. The product is especially applicable to deep treatment of micro-polluted source water, desalting pretreatment of seawater, deep treatment and recycling of waste water in the biochemical engineering and medicine 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 a metal-doped g-C 3 N 4 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 cr...

AI Technical Summary

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] From the above, it can be seen that the research on photocatalytic separation membranes at home and abroad is still in the laboratory exploration stage, and the preparation process of visible light-catalyzed ultrafiltration membranes is complicated and difficult to achieve industrialization.

The present invention is passed in g-C 3 N 4 Doped with metal salt to give full play to metal salt and g-C 3 N 4 synergistic effect to further increase g-C 3 N 4 Visible light catalytic activity, and using metal doped g-C 3 N 4 Improve the visible light catalytic properties of polymer ultrafiltration membranes, prepare hollow fiber 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, nor have they been seen at home and abroad. Related literature reports