Zahra Maghsoud - Chemical Engineering Group, Ferdowsi University, Mashhad, Iran
M. H. Navid Famili - Polymer Engineering Group, Tarbiat Modares University, Tehran, Iran
Sayed Siavash Madaeni - Chemical Engineering Faculty, Razi University, Kermanshah, Iran

During the recent decade many studies related to modification of polymeric membranes using inorganic nanoparticles have been made.[1-2] The application of nanoparticles does notalways result in the improvement of membrane performance and in some cases reduction of permeation and/or rejectionhas been reported [3]. The surface properties of nano particles seems to have a major influence on membrane performance, however this factor has not been studied as much as nanoparticle loading. Here we have prepared polyvinylchloride (PVC) nanofiltration membranes from PVC/THF:DMF/water system and studied the effect of nano silica with different surface properties on membrane performance.