Forward Osmosis

Extremely Resistant to Degradation by Draw Solutions & Harsh Chemicals

Ionomr’s polymers are extremely resistant to degradation by draw solutions and other harsh chemicals making them attractive for development of resistant membranes or coatings in the polar-aprotic solvents used in forward osmosis (FO). The properties are highly flexible with ability to tune hydrophilicity and charge.

Forward osmosis is an emerging membrane technology that utilizes osmotic pressure difference to drive water transport through a semi-permeable membrane from the lower osmotic pressure side (lower salinity feed solution) to the higher osmotic pressure side (higher salinity draw solution). Compared to pressure driven filtration processes such as NF and RO, FO can achieve high rejection in a wide range of solutes and contaminants while requiring minimal hydraulic pressure.

However, advancement of the FO process has been hindered by the lack of suitable membranes that provide high water flux and excellent solute rejection. Since the solute and water flux are in the same direction, the design of the selective and support layers must be optimized to provide high water permeability and solute rejection in the selective layer and minimal diffusion resistance in the support layer.