Development of a Lycopodium powder-based superhydrophobic nanofiber membrane suitable for desalination

A biobased, green, inexpensive additive, Lycopodium particles, which are spores of the Lycopodium clavatum plant, were incorporated in the poly(vinylidene fluoride) PVDF electrospun nanofiber membranes (ENMs) for desalination by direct contact membrane distillation (DCMD). Superhydrophobic ENMs were prepared using this additive (PVDF-ENMs-Lyc). Thanks to their morphological structure and their prominent surface super-hydrophobicity (anti-wetting) character, the resulting PVDF-ENMs-Lyc exhibited an improved liquid entry pressure (LEP), a high void volume fraction (greater than 87.2%), a good salt rejection factor (greater than 99.93%) and a reasonably high permeate flux (greater than 51.76 kg center dot m(-2)center dot h(-1)) at 80 degrees C, which are of great practical importance for water desalination by DCMD. The optimum membrane prepared with 3 wt% Lycopodium in the dope solution demonstrated a stable permeate flux of 52.4 +/- 0.6 kg center dot m(-2)center dot h(-1) with an electrical conductivity around 4.76 +/- 0.46 mu S/cm (NaCl rejection factor of 99.998 +/- 0.036%) during 25 h DCMD desalination experiment using 35 g/L NaCl aqueous solution (similar to seawater concentration). The presented results pave the way for superhydrophobic nanofibrous membrane engineering suitable for membrane contactors by electrospinning in a single step without surfactants, organic additives, or chemical post-treatments, just by the incorporation of a green additive like Lycopodium powder.

Automated summary

The study incorporated Lycopodium particles into PVDF nanofiber membranes to create superhydrophobic membranes. These membranes showed improved liquid entry pressure, high void volume fraction, good salt rejection factor, and reasonably high permeate flux, making them suitable for water desalination.