Porous Organic Polymers for Efficient and Selective SO 2 Capture from CO 2 -rich Flue Gas.

The quest for effective technologies to reduce SO 2 pollution is crucial due to its adverse effects on the environment and human health. Markedly, removing a ppm level of SO 2 from CO 2 -containing waste gas is a persistent challenge, and current technologies suffer from low SO 2 /CO 2 selectivity and energy-intensive regeneration processes. Here using the molecular building blocks approach and theoretical calculation, we constructed two porous organic polymers (POPs) encompassing pocket-like structures with exposed imidazole groups, promoting preferential interactions with SO 2 from CO 2 -containing streams. Markedly, the evaluated POPs offer outstanding SO 2 /CO 2 selectivity, high SO 2 capacity, and an easy regeneration process, making it one of the best materials for SO 2 capture. To gain better structural insights into the notable SO 2 selectivity of the POPs, we used dynamic nuclear polarization NMR spectroscopy (DNP) and molecular modelling to probe the interactions between SO 2 and POP adsorbents. The newly developed materials are poised to offer an energy-efficient and environment-friendly SO 2 separation process while we are obliged to use fossil fuels for our energy needs.