Benzonquanmine-based hypercrosslinked polymers for high-efficiency and reversible iodine capture

Designing and preparing of materials for highly efficient and reversible iodine adsorption remains a challenging task. In this study, a series of benzonquanmine-based hypercrosslinked polymers (BHCPs) with nitrogen-rich were designed and synthesized via Friedel-Crafts reaction. The obtained BHCPs showed the high specific surface and high thermal stability. Moreover, the BHCP-3 of BHCPs exhibits excellent iodine capture performance, including ultrahigh iodine vapor adsorption capacity of 619 wt%, the breakthrough iodine experiment of the adsorption capacity reached 2.29 g/g, which is the highest published capacity of HCP adsorbent. And the removal rate of iodine in aqueous solution also reached 92.5 %, and reached 87.4 % the first 10 min, demonstrating rapid adsorption effects. Additionally, the iodine adsorption process of BHCPs conformed to the pseudo-second-order kinetic models, and which were a multi-layer adsorption on non-homogeneous surfaces. Furthermore, the three adsorbents maintained more than 85 % of their iodine capture capacity after five cycles, demonstrating their good recyclability and potential for practical applications.