Development of novel nanofiltration (NF) membranes for selective separation between organics and inorganics

The objective of this study is to develop novel nanofiltration (NF) membranes for selective separation between organics and inorganics, with the final goal of developing a tailor-made NF membrane design based on polyelectrolytes .

Complex brines of different industrial processes offer great potential for resource recovery, but this recovery is often hampered by the fact that salts cannot be directly recovered due to a large fraction of organics present, whereas the organics can not be valorized (e.g., as biogas) due to the high inorganic content. As such, there is an urgent need for selective membranes and processes that allow separation of such complex brines into an inorganic and an organic stream. This project will go beyond the state-of-the-art by using a platform technology of layer-by-layer polyelectrolyte architectures to prepare tailor-made nanofiltration membranes. The first phase of the project will consist of a screening of a wide range of polymeric materials for their interaction energy with a wide range of organic pollutants. This screening will be based on a toolbox of polyelectrolytes varying in ionic charge character, charge density and hydrophobicity, as revealed by rigorous characterization of streaming potential/current data and contact angle. These membranes will be produced as a composite membrane on hollow fiber geometries. The second phase of the research will consist of development of membranes preferentially as thin film composites synthesized in a membrane fabrication process called “Chemistry-in-a-spinneret”. Membranes spinning parameters will be tuned to tailor pore size of the top layers to pass salts to as high an extent as possible.