Membrane desalination using surface fluorination treated electrospun polyacrylonitrile membranes with nonwoven structure and quasi-parallel fibrous structure

Polyacrylonitrile (PAN) solution was electrospun into fibrous membranes with nonwoven structure and quasi-parallel fibrous structure using a rotating drum collector. Surface fluorination treatment technique was applied to transform the intrinsically hydrophilic PAN membranes into hydrophobic membranes. A set of surface fluorination treated electrospun PAN membranes were tested for membrane desalination (MD) using a lab-scale air gap membrane desalination system . The results show that it is promising to use intrinsically non-hydrophobic membranes in MD after surface fluorination modification based on permeate flux and salt rejection ratio. In the MD application , we found that the fiber orientation combing with the flow direction of the feed could affect the mass transfer performance. The quasi-parallel fiber alignment , surface fluorination treatment, liquid entry pressure , permeate flux, and mass transfer coefficient were studied in detail in this work.