title: CO Separation from H2via Hydrate Formation in Single-Walled Carbon Nanotubes.
abstract: Hydrogen is an alternative fuel without generating greenhouse gas or other harmful emissions. Industrial hydrogen production, however, always contains a small fraction of carbon monoxide (CO) (∼0.5-2%) that must be removed for use in fuel cells. Here, we present molecular dynamics simulation evidence on facile separation of CO from H2at ambient pressure via the formation of quasi-one-dimensional (Q1D) clathrate hydrates within single-walled carbon nanotubes (SW-CNTs). At ambient pressure, Q1D CO (or H2) clathrates in SW-CNTs are formed spontaneously when the SW-CNTs are immersed in CO (or H2) aqueous solution. More interestingly, for the CO/H2aqueous solution, highly preferential adsorption of CO over H2occurs within the octagonal or nonagonal ice nanotubes inside of SW-CNTs. These results suggest that the formation of Q1D hydrates within SW-CNTs can be a viable and safe method for the separation of CO from H2, which can be exploited for hydrogen purification in fuel cells.
authors.affiliation: Department of Physics, Ningbo University , Ningbo, Zhejiang 315211, China.|Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, China.
authors.forename: Wenhui
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Department of Chemistry, University of Nebraska-Lincoln , Lincoln, Nebraska 68588, United States.
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Francisco
authors.affiliation: Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemical Physics, University of Science and Technology of China , Hefei, Anhui 230026, China.|Department of Chemistry, University of Nebraska-Lincoln , Lincoln, Nebraska 68588, United States.
authors.forename: Xiao Cheng
authors.initials: XC
authors.lastname: Zeng