Two nitrogen-rich conjugated microporous polymers for efficient iodine sequestration and removal

Conjugated microporous polymers (CMPs) have attracted great interest due to their high surface area, porosity and conjugacy, which could be potentially applied in pollutant adsorption, heterogeneous photocatalysis and super capacitor. Iodine 129 ( 129 I) and iodine 131 ( 131 I), as the common volatile radioactive products in nuke waste, have a long radioactive half-life, which is an important issue all the time. Here, two novel conjugated microporous polymers (TPAsTr-CMP and TPAPyD-CMP), which are rich in N element, were synthesized via Suzuki reaction and characterized through FTIR, 13 C NMR, SEM, TGA and etc. The surface areas calculated by BET are 449.1 m 2 /g for TPAsTr-CMP and 15.6 m 2 /g for TPAPyD-CMP, respectively. The iodine adsorption experiments at 350 K exhibited that the iodine uptake of TPAsTr-CMP was up to 3.52 g/g; while TPAPyD-CMP had the iodine uptake of 2.84 g/g. For dissolved iodine in cyclohexane, the TPAPyD-CMP performed a better adsorption capacity than TPAsTr-CMP. The adsorption capacity of TPAPyD-CMP was 333.8 mg/g, when initial iodine concentration was 500 mg/L, while that of TPAsTr-CMP was only 104.3 mg/g. The adsorption capacity to iodine should be attributed to their high surface area, effective adsorptive sites and expanded π-conjugated network.