The Preparation Of Polysulfone Membrane And Application On Wastewater Treatment Of Printing And Dyeing

Polysulfone(PSf) ultrafiltration membranes were prepared from a series of casting solutions with different composition by phase inversion process. Dimethylacetamide (DMAc)/polyethyleneglycol(PEG)were used as casting solvent and water was used as coagulant. The resulting membranes prepared by changing the polymer concentration(in the range of 15-20wt%),the molecular weight (400,600,800Da)of PEG additive and the ratio of PEG were characterized by mechanical 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 increased 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 PEG. The experimetal parameters are investigated by using orthoanal experiment. Based on the experiment results, the optimized PSf menbrane is made.In order to strengthen the hydrophility of Poly(sulfone) ultrafiltration membrane surface and rise its anti-fouling property, hydrophobic polysulfone membranes were modified by UV irradiation in 450ml/l ethanol. The structure and conformation carryout does not monomer of membrane on Its surface was characterized by strength of break, contact angle,FTIR,SEM and flux.The results showed that the strength of break reduces and their hydrophilicity increased with increasing in irradiation time. The water flux of menbranes which was irradiation goes up and retention reduce greatly.The contact angle of grafted membrane surface reduces,which show that the hydrophilicity of membrane surface strengthened. FTIR analysis confirmed that new functional group was grafted on the membrane surface. SEM experiment approved that the grafted chain was on the surface not within the pore.On the basis of experiment above,the PSf ultrafiltration membrane was employed for wastewater treatment of printing and dyeing. The effect of treatment was characterized by removal of COD ,turbidity and the color removeal in the wastewater .The experimental results that mean removal rate of COD is over 62%,the turbidity can be removed 94%,and the color removal rate is over 87%.The operated pressure 0.04MP was selected by the experiment operation,and the gel layer model of disposing wastewater has been found,the equation isΔP/(uJ_W)=0.18063×10¹²V + 11.0436×10¹².The research results provide a theroy basis for the optimization for preparation of PSf 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.