Synthesis of N-containing porous aromatic frameworks via Scholl reaction for reversible iodine capture

The effective capture of radioactive volatile iodine ( 131 I and 129 I) from nuclear waste stream is of vital significance. In this work three kinds of porous organic frameworks (POFs) knitting with N -containing building units were constructed via cost-effective and maneuverable Scholl reaction. The obtained PAFs exhibited moderate porosity and satisfying thermal stability. With coexistence of open porous structure, the electron-rich amino group featured with π-π interactions was found to improve the affinity to iodine, and the iodine uptake capacities were 408 wt%, 335 wt% and 268 wt% when the prepared POFs of P-DPDA, P-TPB and P-PC were employed for the adsorption experiments. The results were superior to most of the porous adsorbents including zeolite , metal-organic frameworks (MOFs) and porous organic polymers (POPs). Iodine adsorption capacities of 289.50 mg g −1 (for P-DPDA), 194.63 mg g −1 (for P-TPB) and 259.69 mg g −1 (for P-PC) in organic solution were achieved, and the adsorbed iodine molecules could be released to ethanol. Such promising and cost-effective materials can be envisaged for application in the field of nuclear waste management.