(397a) Laser Induced Graphene (LIG) Membranes for Light Gas Separations

This work reports the application of Laser-Induced Graphene (LIG) membranes fabricated on commercial asymmetric polysulfone (PSu) for the purification of hydrogen gas from mixtures with carbon dioxide or nitrogen gas. The graphene’s selectivity-boosting effects are further examined by the removal of LIG layer on PSu and with membrane reorientation to assess the separation mechanism. Our prior work demonstrated both high permselectivity and permeance for LIG-PSu membranes in the separation of hydrogen from carbon dioxide [1], which was attributed to the combination of molecular sieving in the LIG layer and solution diffusion mechanism through the underlying PSu layer. These LIG-polymer membranes are low cost and can be scaled up, showing promise for selective separation of hydrogen.

In this study, we investigate the impact of flow configuration, co-species and individual membrane layers upon the LIG-PSu membrane performance, with an aim to better understand the underlying transport mechanism for selective H₂/CO₂separation. Specifically, we investigate the hydrogen, carbon dioxide and nitrogen permeances in untreated PSu, LIG/PSu and finally LIG/PSu after mechanical removal of the LIG layer. Likewise, the multi-layer LIG/PSu separation properties are assessed under different flow configurations, to distinguish whether the LIG layer, or the LIG/PSu interface, is facilitating gas transport.

[1] N K. Mishra, N. Patil, M. Anas, X. Zhao, B. A. Wilhite, M. J. Green, Highly selective laser-induced graphene (LIG)/polysulfone composite membrane for hydrogen purification, Applied Materials Today, Volume 22, 2021, 100971, ISSN 2352-9407, ttps://doi.org/10.1016/j.apmt.2021.100971