Conventional flat-sheet and hollow fibers membranes are widely being used in pressure-driven osmosis (Reverse Osmosis - RO) applications due to their superior permselectivity. Owing to high operating/maintenance costs required for RO process, alternative processes with less-energy intensive nature have been under investigation by leading membrane scientists. One of such processes, called Forward Osmosis (FO), uses an osmotic pressure difference instead.

For more, read here: Nanofibers make forward osmosis process cheaper