Reaction-induced macropore formation enabling commodity polymer derived carbons for CO 2 capture

• Published in: New journal of chemistry 2023-01, Vol.47 (3), p.1318-1327
• Main Authors: Guillen Obando, Alejandro, Robertson, Mark, Smith, Paul, Jha, Surabhi, Patton, Derek L., Qiang, Zhe
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/D2NJ05434E

CO 2 capture from industrial point source waste streams represents an important need for achieving the global goal of carbon-neutrality. Compared with conventional liquid sorbents, solid sorbents can exhibit several distinct advantages, including enhanced lifetime and reduced energy consumption for sorbent regeneration. Considering that reducing CO 2 emission is a great challenge, reaching approximately 37 billion metric tons just in 2021, ideal sorbent solutions should not only exhibit a high capture performance but also enable large scale manufacturing using low-cost precursors and simple processes. In this work, we demonstrate the use of a commodity polymer, polystyrene- block -polyisoprene- block -polystyrene (SIS), as the starting material for preparing hierarchically porous, sulfur-doped carbons for CO 2 capture. Particularly, the sulfonation-crosslinking reaction enables the formation of macropores in the polymer framework due to the release of gaseous byproducts. After carbonization and activation, the highly porous structure of SIS-derived carbons is successfully retained, while their surface area can reach up to 905 m 2 g −1 . These porous carbon sorbents exhibit excellent CO 2 uptake performance, reaching sorption capacities of 3.8 mmol g −1 at 25 °C and 6.0 mmol g −1 at 0 °C, as well as a high selectivity up to 43 : 1 against N 2 gas under ambient conditions. Overall, our work provides an industrially viable method for “template-free” fabrication of porous carbons from commodity polyolefin-based materials, which can be employed for reducing CO 2 emission from industrial plants/sectors.