Water scarcity is one of the greatest global crises of our time. Increasing water supply beyond what is available from the hydrological cycle can be achieved by seawater desalination and wastewater reuse. Highly effective, low-cost, robust membrane-based technologies for desalination and wastewater reuse are needed, with minimal impact on the environment. However, progress in current state-of-the-art water purification membranes has been limited. This presentation will critically discuss and evaluate recent research efforts in the past 15 years to (i) lower energy consumption for water desalination by improving membrane water permeability, (ii) reduce the cost of water desalination via increased water-salt selectivity, and (iii) enhance membrane ion selectivity for applications at the water-energy nexus. The presentation will highlight the emerging area of ion selectivity where high precision ion separation is desired. We will discuss how insights from nanofluidics and ion-selective biological channels establish the basis for a new class of membranes with ion-ion selectivity. A few examples will be provided to elucidate the mechanisms of ion transport and selectivity in membranes with sub-nanometer pores. The presentation will conclude with a discussion on research directions and critical challenges for developing ion-selective membranes.
Bio: Menachem Elimelech is the Sterling Professor of Chemical and Environmental Engineering at Yale University. His research focuses on membrane-based processes for energy-efficient desalination and wastewater reuse, advanced materials for next-generation separation and water decontamination technologies, and environmental applications of nanomaterials. Professor Elimelech was the recipient of numerous awards in recognition of his research contributions. Notable among these awards are the 2005 Clarke Prize for excellence in water research; election to the US National Academy of Engineering in 2006; Eni Prize for ‘Protection of the Environment’ in 2015; and election to the Chinese Academy of Engineering in 2017, the Australian Academy of Technology and Engineering in 2021, and the Canadian Academy of Engineering in 2022. Professor Elimelech has advised 49 PhD students and 45 postdoctoral researchers, many of whom hold leading positions in academia and industry. In recognition of his excellence in teaching and mentoring, he received the W.M. Keck Foundation Engineering Teaching Excellence Award in 1994, the Yale University Graduate Mentoring Award in 2004, and the Yale University Postdoctoral Mentoring Prize in 2012.