Performance of amine-multilayered solid sorbents for CO2 removal: Effect of fabrication variables

The emission of fossil fuel carbon dioxide (CO2) to the atmosphere is implicated as the predominant cause of global climate change; therefore, advanced CO2 capture technologies are of the utmost importance. In this study, innovative amine-multilayered sorbents were fabricated using layer-by-layer (LbL) nanoassembly technology via alternate deposition of a CO2-adsorbing amine polymer (e.g. polyethylenimine or PEI) and an oppositely-charged polymer (e.g. polystyrene sulfonate or PSS). We found that the developed sorbents could be used for CO2 capture and that LbL nanoassembly allows us to engineer their CO2 capture performance through the fabrication variables (e.g. deposition polymers, deposition media, and number of bilayers). PEI/PSS was found to be the best polymer combination for developing sorbents with relatively high CO2 capture capacity. The amine-multilayered solid sorbents possessed fine microstructures and may have similar polymer deposition within and on the surface of solid sorbents. These amine-multilayered sorbents had much faster CO2 desorption rates compared to sorbents prepared using the current PEI-impregnation approach. Such fast CO2 desorption could make sorbents a good option for CO2 removal from power plants and even the atmosphere. (C) 2011 Elsevier Ltd. All rights reserved.