2014 R&D 100 Winner
Membrane technologies are crucial in a variety of separation processes, from biotechnology to energy. Current membrane developments are bottlenecked by the “selectivity vs permeability paradox”. That is, the higher selectivity achieved by use of small pores (of less than 0.5 nm) is compromised by the lower permeability flux, and vice versa. This is especially evident in parasitic energy loss for ethanol-water separations. A new type of nanomembrane, Oak Ridge National Laboratory’s High-Performance Architectured Surface Selective (HiPAS) membranes combine a superhydrophobic surface selectivity layer with an architectured high-flux membrane layer to eliminate this Catch-22.
Two enabling technologies allow HiPAS to outperform existing zeolite and polymer-based membranes. First, a surface selectivity layer (S-layer) has been designed with new superhydrophobic/superhydrophilic technology that allows tunable wettability without having to reduce pore size below 1 nm.
Hierarchical pore design minimizes selectivity loss. Second, an architectured high-flux membrane layer has been developed with nanochannels that provide a 104-order-of-magnitude enhancement of flux over previous technologies. These layers are placed on top of a porous membrane support platform suitable for high-throughput industrial processing. Because the two nanostructured layers can be integrated with established ORNL inorganic membranes as supports the potential is good for scale-up and implementation in follow-on commercialization efforts.
Oak Ridge National Laboratory
|Oak Ridge National Laboratory's High-Performance Architectured Surface Selective (HiPAS) development team (l-r): Tim theiss, Michael Hu, Tolga Aytug and Brian Bischoff.|
The High-Performance Architectured Surface Selective (HiPAS) membranes Development Team from Oak Ridge National Laboratory
Michael Z. Hu, Principal Developer
Ramesh R. Bhave
Brian L. Bischoff
Matthew R. Sturgeon
Tim J. Theiss