Nanocrystalline cellulose reinforced PVDF-HFP membranes for membrane distillation application

Polyvinylidenefluoride-co-hexafluoropropylene (PVDF-HFP) membranes containing different amounts of nanocrystalline cellulose (NCC) were fabricated by electrospining technique for application in membrane distillation (MD). The effect of incorporating NCC on the mechanical strength, morphology, pore size distribution, and liquid entry pressure (water) of the fibrous was investigated. Incorporation of NCC in PVDF-HFP matrix improved the tensile strength and Young's modulus and narrowed down the pore size distribution of the fabricated membranes. Liquid entry pressure, which is an important parameter to ensure high salt rejection of the membranes in MD, was improved from ~19psi to ~27psi with the addition of 2wt.% NCC. Fabricated membranes were tested in direct contact membrane distillation (DCMD). MD operation data revealed water flux of 10.2-11.5 Lh^-1m^-2 with salt rejection of 99% for these NCC-incorporated membranes.