A superhydrophobic nanofiber membrane and its application to dye filtration using membrane distillation

Abstract

Direct contact membrane distillation tests are carried out on four kinds of dye solutions using the superhydrophobic polyvinylidene difluron-copolymerized hexafluoro-propylene nanofiber membrane (PH-E) and its modification coated with polydime-thylsiloxane (PDMS) nanoparticles (PDMS-PH-E membrane). The test results show that PDMS-PH-E membrane has higher water flux, and the removal efficiency of four dyes reaches 100%. While the removal efficiency of the PH-E membrane reaches 100% only for two dyes. The loosely absorbed dye structure on PDMS-PH-E membrane roughens the surface, and stimulates the negatively charged droplets to bounce, resulting in an effective anti-fouling and self-cleaning effect and a long-term scaling prevention.