Mohammadreza Moshtagh - Department of Chemical Engineering, Amirkabir University of Technology, No. ۴۲۴, Hafez Ave., Tehran, Iran
Farzin Zokaee Ashtiani - Department of Chemical Engineering, Amirkabir University of Technology, No. ۴۲۴, Hafez Ave., Tehran, Iran
Mohammad Karimi - Department of Textile Engineering, Amirkabir University of Technology, No. ۴۲۴, Hafez Ave., Tehran, Iran

This study aims to compare the effect of concentration hydrophobic surface modifying macromolecules (SMMs) on composite hydrophobic/ hydrophilic membrane and desalination performance by direct contact membrane distillation (DCMD). Two different SMMs concentration are used for the polyethersulfone (PES) as host polymer. The membranes were characterized using a variety of characterization techniques including the LEPw, SEM and contact angle measurement. Moreover, the membranes were tested by DCMD for desalination of 42g/l NaCl solution. According to the results, SMMs migrated to the surface and effectively increased the surface hydrophobicity of PES membranes. It was found that increasing the SMMs concentration increase the permeate flux of the porous composite hydrophobic/hydrophilic membranes and although the value of LEPw increased. Increase in surface contact angle was also observed.

Direct contact membrane distillation; Surface-modifying macromolecules; Composite membranes; polyethersulfone