1. Facilely Cross-Linking Polybenzimidazole with Polycarboxylic Acids to Improve H2/CO2 Separation Performance
- Author
-
Leiqing Hu, Haiqing Lin, Liang Huang, Rajinder P. Singh, and Vinh T. Bui
- Subjects
chemistry.chemical_classification ,Materials science ,Oxalic acid ,Doping ,02 engineering and technology ,Polymer ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Membrane ,chemistry ,Chemical engineering ,General Materials Science ,0210 nano-technology ,Selectivity ,Syngas - Abstract
Polybenzimidazole (PBI) with a strong size-sieving ability exhibits attractive H2/CO2 separation properties for blue H2 production and CO2 capture. Herein, we report that PBI can be facilely cross-linked with polycarboxylic acids, oxalic acid (OA), and trans-aconitic acid (TaA) to improve its separation performance. The acids react with the amines on the PBI chains, decreasing free volume and increasing size-sieving ability. The acid doping increases H2/CO2 selectivity from 12 to as high as 45 at 35 °C. The acid-doped samples demonstrate stable H2/CO2 separation performance when challenged with simulated syngas containing water vapor at 150 °C, which surpasses state-of-the-art polymers and Robeson's upper bound for H2/CO2 separation.
- Published
- 2021
- Full Text
- View/download PDF