Selectivity

Organic chemistry

Metal-organic framework

Hydrogen

Hydrogen bond

Crystal structure

Nuclear chemistry

Adsorption

Engineering

Catalysis

Inorganic chemistry

Chemistry

Isostructural

Gallate

Sulfur dioxide

Hydrogen sulfide

Molecule

Sulfur

Chemical engineering

Flue-gas desulfurization

Journal of the American Chemical Society

Selective elimination of sulfur dioxide is significant in flue gas desulfurization and natural gas purification, yet developing adsorbents with high capture capacity especially at low partial pressure as well as excellent cycling stability remains a challenge. Herein, a family of isostructural gallate-based MOFs with abundant hydrogen bond donors decorating the pore channel was reported for selective recognition and dense packing of sulfur dioxide via multiple hydrogen bonding interactions. Multiple O···H–O hydrogen bonds and O···H–C hydrogen bonds guarantee SO2 molecules are firmly grasped within the framework, and appropriate pore apertures afford dense packing of SO2 with high uptake and density up to 1.86 g cm–3, which is evidenced by dispersion-corrected density functional theory calculations and X-ray diffraction resolution of a SO2-loaded single crystal. Ultrahigh adsorption uptake of SO2 at extremely low pressure (0.002 bar) was achieved on Co-gallate (6.13 mmol cm–3), outperforming all reported state-of-the-art MOFs. Record-high IAST selectivity of SO2/CO2 (325 for Mg-gallate) and ultrahigh selectivity of SO2/N2 (>1.0 × 104) and SO2/CH4 (>1.0 × 104) were also realized. Breakthrough experiments further demonstrate the excellent removal performance of trace amounts of SO2 in a deep desulfurization process. More importantly, M-gallate shows almost unchanged breakthrough performance after five cycles, indicating the robust cycling stability of these MOFs.

Deep Desulfurization with Record SO<sub>2</sub> Adsorption on the Metal–Organic Frameworks

Deep Desulfurization with Record SO2 Adsorption on the Metal–Organic Frameworks

Deep Desulfurization with Record SO₂ Adsorption on the Metal–Organic Frameworks