摘要：SummaryIn this study, the concept of biomass-based direct air capture is proposed, and the aminoguanidine CO2chemical sorbent 2,5-furan-bis(iminoguanidine) (FuBIG) was designed, synthesized, and elucidated for the physicochemical properties in the process of CO2capture and release. Results showed that the aqueous solution of FuBIG could readily capture CO2from ambient air and provided an insoluble tetrahydrated carbonate salt FuBIGH2(CO3) (H2O)4with a second order kinetics. Hydrogen binding modes of iminoguanidine cations with carbonate ions and water were identified by single-crystal X-ray diffraction analysis. Equilibrium constant (K) and the enthalpies (ΔH) for CO2absorption/release were obtained by thermodynamic and kinetic analysis (K7 = 5.97 × 104, ΔH7 = −116.1 kJ/mol, ΔH8 = 209.31 kJ/mol), and the CO2-release process was conformed to the geometrical phase-boundary model (1-(1-α)1/3 = kt). It was found that the FuBIGH2(CO3) (H2O)4can release CO2spontaneously in DMSO without heating. Zebrafish models revealed a favorable biocompatibility of FuBIG.Graphical abstractDisplay OmittedHighlights•The concept of biomass-derived direct air capture has been proposed and reinforced by the sorbent of FuBIG•The sorbent revealed favorable thermodynamic and kinetic parameters for CO2 capture and release•The sorbent has excellent biocompatibility and good thermostability•FuBIG carbonate can release CO2and regenerate FuBIG spontaneously in DMSO without heatingChemistry; Organic Synthesis; Natural Product Chemistry; Environmental Science; Pollution; Biomaterials
