Desalination by forward osmosis using nonionic surfactants

Abstract

An adequate and dependable supply of fresh water is critical for human health and prosperity. As traditional water resources have become scarcer, processing seawater into fresh water has become essential for many nations. Recent advances in membrane technologies have enhanced the viability of desalination strategies that employ semipermeable barriers. Forward osmosis (FO), which exploits the natural osmotic pressure gradient between a solution and saline to produce potable water, offers a low-energy, low-cost alternative to more conventional desalination methods. Explored herein is the use of t-octylphenoxypolyethoxyethanol surfactants as osmotic agents in draw solutions. Surfactants, because of their tendencies to aggregate into micelles and to adsorb at interfaces, offer exploitable properties by which draw solutions can be regenerated. The effectiveness of surfactant-based FO using Hydration Technology Innovations cellulose triacetate membranes has been assessed in terms of water flux and revers...