title: A bio-metal-organic framework for highly selective CO(2) capture: A molecular simulation study.
abstract: A recently synthesized bio-metal-organic framework (bio-MOF-11) is investigated for CO(2) capture by molecular simulation. The adenine biomolecular linkers in bio-MOF-11 contain Lewis basic amino and pyrimidine groups as the preferential adsorption sites. The simulated and experimental adsorption isotherms of pure CO(2), H(2), and N(2) are in perfect agreement. Bio-MOF-11 exhibits larger adsorption capacities compared to numerous zeolites, activated carbons, and MOFs, which is attributed to the presence of multiple Lewis basic sites and nano-sized channels. The results for the adsorption of CO(2)/H(2) and CO(2)/N(2) mixtures in bio-MOF-11 show that CO(2) is more dominantly adsorbed than H(2) and N(2). With increasing pressure, the selectivity of CO(2)/H(2) initially increases owing to the strong interactions between CO(2) and the framework, and then decreases as a consequence of the entropy effect. However, the selectivity of CO(2)/N(2) monotonically increases with increasing pressure and finally reaches a constant. The selectivities in bio-MOF-11 are higher than in many nanoporous materials. The simulation results also reveal that a small amount of H(2)O has a negligible effect on the separation of CO(2)/H(2) and CO(2)/N(2) mixtures. The simulation study provides quantitative microscopic insight into the adsorption mechanism in bio-MOF-11 and suggests that bio-MOF-11 may be interesting for pre- and post-combustion CO(2) capture.
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore.
authors.forename: Yifei
authors.initials: Y
authors.lastname: Chen
authors.forename: Jianwen
authors.initials: J
authors.lastname: Jiang
mesh_terms: D000225:Adenine / Q000737:chemistry; D000327:Adsorption; D002245:Carbon Dioxide / Q000737:chemistry* / Q000302:isolation & purification*; D057965:Carbon Sequestration; D006859:Hydrogen / Q000737:chemistry; D058115:Lewis Bases / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D009584:Nitrogen / Q000737:chemistry; D009930:Organic Chemicals / Q000737:chemistry*; D016062:Porosity; D011743:Pyrimidines / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D058115:Lewis Bases; D008670:Metals; D009930:Organic Chemicals; D011743:Pyrimidines; D014867:Water; D002245:Carbon Dioxide; D006859:Hydrogen; D000225:Adenine; C030986:pyrimidine; D009584:Nitrogen