Surface-dissociated nanoparticle draw solutions in forward osmosis and the regeneration in an integrated electric field and nanofiltration System

Abstract

Draw solutions of surface-dissociated nanoparticles in forward osmosis (FO) processes and their regeneration through an integrated electric field-nanofiltration system for water reclamation were explored for the first time. Nanoparticles of 20 nm in diameter were functionalized with different surface chemistries to systematically investigate the effects on the FO performance. Experimental results showed that the draw solutions of surface-dissociated nanoparticle prepared with alkalis exhibited higher osmotic driving forces. Compared to salt base draw solutes, the advantage of surface-dissociated nanoparticle draw solutes exhibits no reverse flux across the FO membrane. The diluted draw solution of surface-dissociated nanoparticles can be readily recovered via an integrated electric field and nanofiltration system with sustainable regeneration efficiency. Our preliminary results suggest the potential of surface-dissociated nanoparticles as draw solutes in FO for water reuse. © 2012 American Chemical Society.