Forward osmosis

In forward osmosis (FO) two liquids of different osmotic pressure are contacted via a semi-permeable membrane. Water transfers towards the chamber with high osmotic pressure while solutes are retained. Most current membranes, developed and optimized for pressure-driven processes, do not perform in FO due to excessive concentration polarization. Major applications are the recovery of drinking water from contaminated water sources, the production of energy from salt concentration differences (e.g. river to seawater) by pressure- retarded osmosis (PRO) or the reduction of fouling in the concentration of landfill leachate. We develop FO membranes which are stable against solvents like butanol, aceton and ethanol and which can be used to enrich butanol from ABE fermentation brooth.

Our research

New membranes for pressure-retarded osmosis power plants

Fraunhofer IGB develops semi-permeable membranes to be used in osmotic power plants for the generation of emission-free energy.