Efficient SO2 Capture through Multiple Chalcogen Bonds, Sulfur‐Centered Hydrogen Bonds and Sπ Interactions: A Computational Study. Issue 8 (9th June 2016) - Sahoo, Dipak Kumar
Abstract: The non‐toxic, environment friendly, biodegradable properties and cost effectiveness of active pharmaceutical ingredients (APIs) allow them to be used as green‐solvents for several applications. The presence of multiple binding sites in the APIs has an additional advantage for the flue gas capture. Herein we report a detailed analysis of efficient SO2 capture by the anions associated with APIs through several strong and weak non‐covalent interactions. The DFT studies and Langmuir adsorption model suggest that the APIs based anions are highly efficient alternatives for SO2 capture at low as well as high partial pressures (0.01 – 0.1 MPa) of SO2 . The absorption capacity can be achieved as much as 5.8 mol SO2 /mol APIs; the best absorption capacity till reported. Our computational results suggest that for the efficient SO2 capture, the enthalpy of absorption (ΔH) should be −65 to −50 kJ.mol −1 ; below this range absorption capacity reduces drastically. This study also emphasizes the importance of weak interactions (Sπ and C−HO and C−HS hydrogen bonds) together with the strong chalcogen bonds to be considered in designing new absorbing materials for SO2 capture. Abstract : Many new strategies have been adopted to capture SO2 with different absorbing materials both by computational and experimental methods. Simulated Langmuir absorption isotherms, NBO and AIM analyses are used to reveal the importance of several non‐covalent interactions at play in designing high SO2 capture materials.