Multi-Functionalization Integration into the Electrospun Nanofibers Exhibiting Effective Iodine Capture from Water

Abstract

Efficient capture of radioiodine from aqueous solutions is of importance for sustainable development of nuclear energy and protection of the environment. However, current adsorbents under exploration suffer from limited adsorption capacity and powder form that are unfavorable for practical applications. Herein, we applied a “multi-functionalization integration” idea to construct novel electrospun fiber adsorbents (N-MOF-PAN fibers) containing cationic quaternary ammonium groups, uncharged amine groups, and porous MOF material (UiO-66-NH2), which in synergy adsorb iodine effectively from both saturated I2 aqueous solution and I3 – aqueous solution. Iodine species (94.6%) could be removed from saturated I2 solution within 180 min, and 98.7% of iodine species were captured from I3 – solution within 240 min. Additionally, the N-MOF-PAN fibers exhibited high iodine uptake capacities of 3.56 g g–1 from a concentrated KI/I2 aqueous solution and 3.61 g g–1 from the Langmuir isotherm model, surpassing many reported iodine adsorbents in the aqueous medium. Characterization and mechanism analysis indicated that multiple active sites simultaneously attribute to the high binding affinity toward iodine species through physical adsorption and chemical adsorption. Furthermore, benefiting from their macroscopic architecture, N-MOF-PAN fibers were used as the adsorption column for dynamic iodine capture with a bed volume of 1490 mL, which is much higher than commercially activated carbons. Overall, this work provides guidance for the development of novel fiber adsorbents for related applications.

Influence of Interfering Ions and Adsorption Temperature on Radioactive Iodine Removal Efficiency and Stability of Ni-MOF-74 and Zr-UiO-66

“…This indicates the homogeneity of the MOF surface causing iodide ions to adsorb in a monolayer fashion. For our alumina-based adsorbents investigated before, a similar trend was observed where the Langmuir model was reported to be a better fit for the equilibrium adsorption of iodine. As is evident from Table , the plot of C e / q e against C e for the Langmuir model yielded a q max of 680 mg/g and a K L value of 0.002 L/mg, whereas the plot of log­( q e ) as a function of log­( C e ) gave rise to a K F value of 1.45 (mg/g)­(L/mg) −1/ n .…”

Triptycene-Based Cationic Porous Organic Polymer for the Swift and Effective Removal of Organic and Inorganic Anionic Water Pollutants

“…Further, TP_iPOP-2 was also tested for the capture of aquated iodine species. Iodine may be present in water in various forms such as iodide (I – ), polyiodides (I n – ), or iodate (IO 3 – ) anions. , To begin, we started with the anion-exchange-based removal of I 3 – from its aqueous solutions using TP_iPOP-2 as the adsorbent. Upon the addition of TP_iPOP-2 to a light brown-colored solution of I 3 – , the color of the solution began to fade over time.…”

Three novel indole-bearing porous organic polymers for efficient iodine capture from both vapor and organic phases

“…XPS spectrum analysis of I 2 @InPOP-3 was carried out. Two types of polyiodide peaks I 5 À (620.7 and 632.2 eV) and I 3 À (618.8 and 630.3 eV) attributed to the splitting of iodine 3d 3/2 and 3d 5/2 orbital levels [47][48][49][50][51] are observed in Fig. 13(a).…”