Simultaneous Effect of Low and High Molecular weight of Polyvinylpyrrolidone on the Polysulfone Ultrafiltration Membrane

Polyvinylpyrolidone(PVP) is a favorite additive with suitable properties in membrane fabrication industry. Different molecular weight of PVP may has various effect on the polysulfone (psf) membrane. Here PVP-K90 and PVP-K25 as a high and low Molecular weight polymeric additive was used in casting solution. Pore size measurement verified all of membranes had 30-36.9nm mean pore radius which determined by filtration velocity method. Results shown membrane containing 5wt% PVPK25 had maximum water flux and mean pore radius. While membrane containing 7wt% PVP-k25 had maximum porosity. Precipitation rate(PR) of membranes increased by addition of PVP-k25 in casting solution so that this factor reach to maximum value for 7wt% PVP-K25. Aslo rejection study demonstrated all membranes could separate PVP-k90 more than 92% while rejection of PVP-k30 was in 30% – 50%.

کلیدواژه ها:

Psf membrane ، Polyvinylpyrrolidone ، Molecular weight ، Ultrafiltration.