A Robust Cage-Based Metal-Organic Framework Showing Ultrahigh SO₂ Uptake for Efficient Removal of Trace SO₂ from SO₂/CO₂ and SO₂/CO₂/N₂ Mixtures

Removal of trace SO₂ from an SO₂-containing product is now receiving increasing attention. However, designing a robust porous adsorbent with high SO₂ adsorption capacity and good SO₂/CO₂ selectivity, as well as validity under humid conditions, is still a challenging task. Herein, we report a porous cage-based metal-organic framework, namely ECUT-111, which contains two distinct cages with apertures of 5.4 and 10.2 angstrom, respectively, and shows high a BET of up to 1493 m²/g and a pore volume of 0.629 cm³/g. Impressively, ECUT-111 enables an ultrahigh SO₂ uptake of up to 11.56 mmol/g, exceeding most reported top-performing adsorbents for such a use. More importantly, complete separation of trace SO₂ from SO₂/CO₂ and SO₂/CO₂/N₂ mixtures, especially under humid conditions, and excellent recycle use were observed for ECUT-111, suggesting its superior application in desulfurization of SO₂-containing products.