The Preparation Of Polyethersulfone Membrane And Modified Research

Polyethersulfone(PES)ultrafiltration membranes were prepared from a series of casting with different composition by phase inversion process.Dimethylacetamide(DMAc)/Polyethylene pyrrolidone(PVP)K30 were uesd as casting solvent and water was uesd as coagulant.The resulting membranes prepared by changing the polymer concentration(in the range of 14-22wt%)and the ratio of PVP were characterized property,scanning electron microscope observations,measurements of water flux and rejection.Results showed that the flux of the membrane decreased while the separation performance for particle solutes inceeased with an increase in polymer concentration.This means that the outer skin layer of the membranes became apparently thicker and denser with increasing polymer concentration.On the other hand,an UF membrane from a dilute polymer solution produced a thin and porous skin layer,leading to a high value of flux but a relatively low percentage of rejection for PVP.The experimetal parameters are investigated by using orthoanal experiment based on the experimenr results,the optimized PES membrane is made.Inorder to enhance the polyether sulphone ultra filter diaphragm's water affinity performance,enhances its anti-pollution however nature,to tested the polyether sulphone membrane which prepared to carry on the modification.In the self-made polyether sulphone ultra filter diaphragm's foundation, an increase different content's nanometer titanium dioxide carries on the blending modification,seeks for the best modified condition,changed the polyether sulphone membrane structure. Mainly inspected the nanometer titanium dioxide increase to the polyether sulphone performance structure influence,has studied around the modification the breaking strength change,through superficial angle of contact methods and so on cryoscope, scanning electron microscope,modified membrane's pure water flux and interception performance attributes around modified the structure performance change situation.Research surface: Increases the different nanometer titanium dioxide content through the test,has discovered when increases 5.3%nanometer titanium dioxide,the modified membrane's flux and the interception rate achieves the optimum condition,has served the modified purpose;The modified membrane's angle of contact and the interception rate determination indicated that the interception rate basic change is not big,the angle of contact changes is small,the wettability has the enhancement;In this experiment,the modified membrane's ratio of viscosities modified membrane's viscosity has not been small,and after an increase nanometer titanium dioxide,the viscosity increases along with the nanometer titanium dioxide's content increases.Through the above craft preparation's polyether sulphone ultra filter diaphragm,uses in the Sewage treatment plant sanitary sewage and industrial waste processing.This experiment as tests the water used take the Songjiang District new town Sewage treatment plant aeration tank's sewage.Inspected around the modified seepage flux,has studied the ultra filter diaphragm in the elimination waste water aspect and so on COD,turbidity, chromaticity performance.Experimental result surface:The seepage flux changes gradually along with the running time is small,but is slightly small after the modified membrane flux reduction scope;Under the different pressure's seepage flux is also different,pressure build-up's membrane's seepage flux also increases,through the movement comparison,has chosen 0.2Mpa is the working pressure;The ultra filter diaphragm to the COD elimination rate is above 80%,the turbidity elimination rate is above 98%,to the chromaticity elimination is above 70%.And restores the effect from two kind of membrane movement flux to look that the modified membrane the flux is higher than in the sludge movement has not changed the membrane the flux,after modified membrane clean,the restoration ratio achieves above 85.31%,but the modified membrane's restoration ratio has not been 68.08%,anti-pollution performance modified membrane obvious good in for modified membrane.For the better understanding membrane's operational aspect, this article has further carried on a more concrete analysis from the membrane pollution resistance aspect,inspected the active sludge filters when the membrane bioreactor two kind of different membrane resistance and various part of resistance accounts for the proportion,inspected in specifically the membrane filtration process,membrane resistance important source,composition and different membrane resistance change,concrete study membrane filtration process tunica media vasorum resistance change characteristic,when membrane filtration short-term movement and long-term movement the membrane resistance and various part of resistance account for the proportion the change situation, analyzed possibly presented these phenomena the reason,has given the suitable explanation.The research results provide a theroy basis for the optimization for preparation of PES membrane and for the improvement and enhance of the performance of membrane.it also provide a prospect for the application of ultrafiltration membranes on wastewater treatment.