Hydrogen has emerged as a clean energy carrier and a pillar of the carbon-negative economy. Its production and delivery may need various purification steps, such as H2/CO2 separation in the pre-combustion carbon capture process and H2/CH4 separation in its co-delivery with natural gas. Membranes with versatile molecular sieving abilities are of great importance to enable the economically viable and environmentally friendly use of H2.
In this presentation, I will describe our recent effort in designing new polymer architectures to achieve this goal. First, nanomaterials of palladium were introduced into polybenzimidazole to form mixed matrix materials to improve H2/CO2 selectivity. More importantly, we demonstrate that nanorods can significantly reduce the required loading to achieve superior gas separation properties while maintaining excellent processability. Increasing the aspect ratio from 1 for nanoparticles to 40 for nanorods decreases the percolation threshold by 30 times from 0.35 to 0.011. Second, I will describe the engineering of free volumes by introducing bottlenecks to enhance the size-sieving ability and microcavities to increase gas diffusivity for H2/CO2 separation, as exampled by in situ growth of metal-organic materials in polybenzimidazole followed by carbonization generating single zinc atoms. The presentation will describe the performance of these nanomembranes when challenged with simulated gas and the relationship between structure and gas transport properties.
Dr. Haiqing Lin received his Ph.D. in chemical engineering from the University of Texas at Austin in 2005 and then joined Membrane Technology and Research, Inc. (MTR) as a senior research scientist. He led projects on natural gas clean-up and CO2/H2 separation membranes (such as Polaris™ membranes). Dr. Lin joined the University at Buffalo (UB) as an assistant professor in 2013 and was promoted to professor in 2021.
His research focuses on advanced polymeric membranes for gas separations (such as carbon capture) and membranes for water purification (such as surface modification and 2D materials). He has published more than 130 peer-reviewed articles and book chapters, and he is a co-inventor of 10 US patents and patent applications. He was a recipient of the NSF CAREER award in 2016, the Innovation Award from the AIChE Separation Division in 2020, and SUNY Chancellor’s Award for Excellence in Scholarship and Creative Activities in 2022.