title: Cross-linking amine-rich compounds into high performing selective CO2 absorbents.
abstract: Amine-based absorbents play a central role in CO2 sequestration and utilization. Amines react selectively with CO2, but a drawback is the unproductive weight of solvent or support in the absorbent. Efforts have focused on metal organic frameworks (MOFs) reaching extremely high CO2 capacity, but limited selectivity to N2 and CH4, and decreased uptake at higher temperatures. A desirable system would have selectivity (cf. amine) and high capacity (cf. MOF), but also increased adsorption at higher temperatures. Here, we demonstrate a proof-of-concept where polyethyleneimine (PEI) is converted to a high capacity and highly selective CO2 absorbent using buckminsterfullerene (C(60)) as a cross-linker. PEI-C(60) (CO2 absorption of 0.14 g/g at 0.1 bar/90 °C) is compared to one of the best MOFs, Mg-MOF-74 (0.06 g/g at 0.1 bar/90 °C), and does not absorb any measurable amount of CH4 at 50 bar. Thus, PEI-C(60) can perform better than MOFs in the sweetening of natural gas.
authors.affiliation: 1] Department of Chemistry, Rice University, Houston, Texas 77005, USA [2] Energy Safety Research Institute, College of Engineering, Swansea University, Singleton Park, Swansea SA2 8PP, Wales, UK.
authors.forename: Enrico
authors.initials: E
authors.lastname: Andreoli
authors.affiliation: Department of Chemistry, Rice University, Houston, Texas 77005, USA.
authors.forename: Eoghan P
authors.initials: EP
authors.lastname: Dillon
authors.affiliation: Department of Chemistry, Rice University, Houston, Texas 77005, USA.
authors.forename: Laurie
authors.initials: L
authors.lastname: Cullum
authors.affiliation: 1] Department of Chemistry, Rice University, Houston, Texas 77005, USA [2] Shared Equipment Authority, Rice University, Houston, Texas 77005, USA.
authors.forename: Lawrence B
authors.initials: LB
authors.lastname: Alemany
authors.affiliation: 1] Department of Chemistry, Rice University, Houston, Texas 77005, USA [2] Energy Safety Research Institute, College of Engineering, Swansea University, Singleton Park, Swansea SA2 8PP, Wales, UK [3] Department of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005, USA.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Barron