Amine-decorated metal-organic frameworks MIL-53(Al) on titanosilicate zeolite ETS-10 for radioactive iodine entrapment

The storage/disposal of the hazardous fission product iodine (I2) from waste of nuclear industries has caused worldwide concerns because of its severely negative impacts on organisms and environments. Therefore, searching for appropriate adsorbent is of great importance for effective capture of radioactive I2. Herein, a series of novel hierarchical adsorbents, composed of the nanoscale Materials of Institute Lavoisier-53(Al) (MIL-53(Al)) or its amine functionalized derivative NH2-MIL-51(Al) onto a supporter Engelhard Titanosilicate-10 (ETS-10) were successfully synthesized via a wet impregnation method. The performance for I2 removal of the absorbents (MIL-53(Al), NH2-MIL-51(Al) and NH2-MIL-51(Al)@ETS-10) were studied as functions of loading amount, morphology and pore structure, respectively. The NH2-MIL-51(Al)@ETS-10 represents the best adsorption performance due to its good cooperative effects including larger surface area, higher load capacity, strong affinity of charge-transfer complexes with I2 (-NH2 or –NH with I). The adsorption capacity of NH2-MIL-51(Al)@ETS-10 could be reached to 1.16 g·g−1 and is ∼ 2.5 and 5 times higher than the NH2-MIL-51(Al) and MIL-51(Al), respectively. The kinetics and isotherms for adsorption could be fitted via pseudo-second-order and Langmuir models, respectively, indicating the strong monolayer chemisorption interactions. The study manifests that the designed material has certain potential for application in I2 entrapment.