Preparation Of Composite Reverse Osmosis Membranes

The separation layer and support membrane of composite reverse osmosis membrane are two different materials,so they can be optimized to achieve the optimal performance of the membrane according to different requirements,therefore it is widely used.This work based on the preparation process of support membrane and separation layer,discussed influence of main preparation process parameters on the support membrane and separation layer performance respectively,lay the foundation for further research.Firstly it is preparation of polysulfone membrane.Take N-methyl pyrrolidone as solvent and polysulfone as solute to prepare casting solution,then prepare support membrane by immersion phase inversion method,discuss the influence of polysulfone concentration,additive content and molecular weight of PEG,coagulation bath composition,coagulation bath temperature and other parameters on the pure water flux,BSA retention rate,porosity and average pore size and other characteristics of support membrane.In the final choose PSF21%,PEG-2000 concentration 8%,coagulation bath composition Wn2o:Wnmp? 10:3,coagulation bath temperature 35? as the preparation parameters of polysulfone membrane.Secondly prepare desalination function layer in the self-made membrane byinterfacial polymerization,then discuss the influence of m-phenylenediamine concentration,trimesoyl chloride concentration,aqueous solution pH,reaction time,temperature and time of heat treatment on the formation of separation layer and performance of composite reverse osmosis membrane,finally the optimal interfacial polymerization process is determined primarily:m-phenylenediamine concentration 2%,trimesoyl chloride concentration 0.08%,aqueous solution pH=9,reaction time 20s,the heat treatment temperature 60 ?,the heat treatment time 10min.Under the preparation process parameters,the reverse osmosis membrane desalination rate is 97.13%,and the flux is 45.23 L/m2.Finally,the effect of the polar non-proton additive DMSO on the flux and desalination rate of reverse osmosis membrane was studied,and the influence factors of the external operating conditions on the reverse osmosis system were summarized.