Solution-reprocessable microporous polymeric adsorbents for carbon dioxide capture

Solution-processable microporous polymers are promising materials for CO₂ capture because of their low synthetic cost and high processability. In this work, we for the first time systematically evaluate the feasibility of two microporous polymers, namely PIM-1 and its hydrolyzed form hPIM-1, as adsorbent materials for postcombustion CO₂ capture. By conducting ternary CO₂/N₂/H₂O breakthrough experiments, PIM-1 demonstrates several promising features: moderate CO₂ working capacity, low water vapor uptake capacity, good moisture resistance, and easy regeneration process. In addition, we have pioneeringly studied the multiple-cycle CO₂ adsorption–desorption induced relaxation effect on soft PIM-1 polymers. Through a simple dissolution–precipitation approach, PIM-1 can restore its BET surface area, CO₂ uptake capacity, and pore-size distribution. The solution reprocessability of PIM-1 demonstrated in this study distinguishes it from other rigid adsorbents and thus offers a new insight for the future design of economically-viable and facilely regenerable adsorbents.