Study On Modification Of Nanomaterials And Polym-m-Phenylenediamine (PMIA) Membrane

In this paper,two kinds of nanomaterials,2-D planar graphene oxide（GO）and homemade ZnO/TiO₂ core-shell photocatalytic nanomaterials were studied to modify PMIA membrane respectively.PMIA/GO,PMIA/ZT composite ultrafiltration（UF）membranes with high rejection rate,superior anti-fouling and excellent recovery rate for bovine serum protein（BSA）solution were prepared and their applications were expanded.The PMIA/GO modified membrane was successfully prepared from graphene oxide（GO）with strong hydrophilic properties via non-solvent-induced phase separation（NIPS）method using deionized water as a gel bath.SEM images show that all the membranes are asymmetric and own tunnel holes.FTIR and XPS characterization showed that GO was successfully introduced into the PMIA membrane and did not fall off during subsequent cleaning.By measuring the dynamic contact angle（DCA）,the membrane PMIA/GO-2possess the superior hydrophilicity.Through a series of performance tests,such as pure water flux,BSA rejection flux,backwash flux and tensile strength,the permeability,anti-fouling ability and mechanical properties of the membrane were evaluated.The results showed that the membrane PMIA/GO-2 possessed the best performance,the pure water flux was 323.5 l m^-2 h^-1,the BSA rejection rate was 93.5%and the mechanical properties were the best.The prepared membrane was applied to isolate proteins under alkaline conditions.The flux and rejection rate of the membrane were almost unaffected under strong alkali conditions.The self-made ZnO/TiO₂ core-shell photocatalytic nanomaterial was introduced into the PMIA membrane.The PMIA/ZT modified membrane was successfully prepared by non-solvent induced phase separation（NIPS）with deionized water as gel bath.SEM images showed that all the membranes were asymmetrical and nodular.Infrared and XPS characterization showed that ZnO/TiO₂ core-shell photocatalytic nanomaterials were successfully introduced into the PMIA membrane,and did not fall off in the subsequent cleaning.Through a series of performance tests,such as dynamic contact Angle,tensile strength,BSA intercept flux and backwash flux,it is concluded that the membrane PMIA/ZT-0.2 has the best hydrophilicity,pure water flux is 205.83 L m^-2 h^-1,BSA rejection rate is 94.00%,and the mechanical properties are the best.The methylene blue（MB）was removed for 6 hours under 500 W xenon lamp,and the removal rate reached 91.3%.Nanomaterials,such as GO,ZnO/TiO₂ core-shell photocatalytic nanomaterials,have shown excellent functionality in the modified membrane of poly（m-benzoyl m-phenylenediamine）.It has better anti-fouling performance,higher pure water flux and excellent mechanical properties and has immeasurable potential value in the field of protein separation.