PVDF Membranes for Membrane Distillation: Controlling Pore Structure, Porosity, Hydrophobicity, and Mechanical Strength

Membrane distillation (MD) is a separation technique involving the nonisothermal transport of water vapor through a porous, hydrophobic membrane. It is a promising desalination technology that may help resolve the global freshwater shortage. To date, no large-scale MD plants have been implemented yet for desalination (Saffarini et al. 2012a, 2012b), as several scientic and technological challenges still hamper its industrial applications (Curcio and Drioli 2005; Khayet 2008). The major barriers include MD membrane and module design, membrane pore wetting, low permeate ow rate, ux decay, as well as uncertain energy and economic performance gures (Saffarini et al. 2012b). These challenges have attracted scientists and engineers striving to achieve the best MD membrane, performance and/or module and process design (Khayet and Matsuura 2001; Suk et al. 2002; Li and Sirkar 2004; Gilron et al. 2007). Among these research attempts, the development or selection of appropriate membrane materials was very important (Guillen-Burrieza et al. 2013; Saffarini et al. 2013).