18 June 2019
New adsorbent for removing harmful greenhouse gas
Published online 13 July 2014
A research team has synthesized a porous, moisture-resistant, copper-based metal-organic framework, in crystalline powder form, that can selectively adsorb and remove trace CO2 from mixtures of various gases — with potential for various industrial applications related to energy, environment and health.
“This newly produced copper-based metal-organic framework could potentially be used for removing low concentrations of carbon dioxide from air in confined space environments such as submarines and space shuttles and in biomedical fields such as anaesthesia,” says team leader Mohammed Eddaoudi from King Abdullah University of Science and Technology (KAUST).
The team published their results in Nature Communications1.
They produced the crystalline powder of the framework by reacting a methanol solution of pyrazine with a methanol solution of hexafluorosilicates. In studies with various combinations of gas mixtures containing CO2, nitrogen and other gases, they found that the powdery adsorbent captured CO2 gas molecules more strongly and rapidly compared to nitrogen, methane and hydrogen molecules.
The copper-based adsorbent’s efficiency is 10 to 15 times higher than the uptakes of CO2 by zinc-based metal-organic adsorbent. The researchers attributed this to physical sorption through electrostatic attraction between CO2 molecules and fluorine atoms present on the surface of the adsorbent.
This innovation is part of a greater, critical effort, the study says, to develop economical and practical pathways to reduce cumulative CO2 emissions, which provoke the undesirable greenhouse effect.
Shekhah, O. et al. Made-to-order metal-organic frameworks for trace carbon dioxide removal and air capture. Nature Commun. doi: http://dx.doi.org/10.1038/ncomms5228