Polyazole Hollow Fiber Membranes for Direct Contact Membrane Distillation

Porous hollow fiber membranes were fabricated from fluorinated polyoxadiazole and polytriazole by a dry–wet spinning method for application in desalination of Red Sea water by direct contact membrane distillation (DCMD). The data were compared with commercially available hollow fiber MD membranes prepared from poly(vinylidene fluoride). The membranes were characterized by electron microscopy, liquid entry pressure (LEP), and pore diameter measurements. Finally, the hollow fiber membranes were tested for DCMD. Salt selectivity as high as 99.95% and water fluxes as high as 35 and 41 L m–2 h–1 were demonstrated, respectively, for polyoxadiazole and polytriazole hollow fiber membranes, operating at 80 °C feed temperature and 20 °C permeate.