Porous Cationic Electrospun Fibers with Sufficient Adsorption Sites for Effective and Continuous ⁹⁹TcO₄⁻ Uptake

Abstract

Removal of radioactive technetium-99 ( 99 TcO 4 − ) from water by effective adsorbents is highly desired but remains a challenge. The currently used resin adsorbents possess several obstacles, such as slow adsorption kinetics and low adsorption capacity. To address these issues, herein a type of fibrous adsorbent with porosity and hyper-branched quaternary ammonium groups, namely porous cationic electrospun fibers (PCE fibers), is successfully prepared. PCE fibers can remove 97% of 99 TcO 4 − within 1 min and the equilibrium time of 99% removal is 20 min. The predicted maximum adsorption capacity toward the surrogate ReO 4 − can reach 826 mg g −1 , which is higher than the state of art anion-exchange resins and most of the other reported adsorbents. Furthermore, PCE fibers have good selectivity for ReO 4 − in the presence of competitive anions, and can retain ReO 4 − uptake under extreme conditions including high acid-base and gamma irradiation. Importantly, PCE fibrous adsorptive membrane is employed for dynamic ReO 4 − removal from simulated Hanford LAW stream with a processing capacity of 600 kg simulated stream per kilogram PCE fibers. The excellent performance highlights the advantages of PCE fibers over traditional resins in technetium removal.

Fabrication and Properties of the Multifunctional Rapid Wound Healing Panax notoginseng@Ag Electrospun Fiber Membrane

“…Electrospun fiber membranes have high porosity and good air permeability, and can efficiently absorb tissue fluid at the wound [ 42 , 43 , 44 ]. Comparing Table 1 and Table 2 , the average swelling ratio of the PN@8 wt%Ag-2 h fiber membrane is significantly higher than that of the PN@8 wt%Ag-NCS fiber membrane, which shows that the addition of CS enhances the hygroscopic property of electrospun fiber membranes.…”

Ultra‐Selective and Efficient Static/Dynamic Palladium Capture from Highly Acidic Solution with Robust Macrocycle‐Based Polymers

“…[55] As such, the adsorption of Pd(II) at high acidity might occur by anion exchange mechanism due to the higher hydrophobicity of anionic Pd(II) complexes and their relatively strong electrostatic interaction with the protonated nitrogen sites on adsorbents. [56] The plethora of anions present in HLLW, such as TcO 4 − as one of the fission products, [57][58][59] SO 4…”

Pyridinium‐Functionalized Ionic Porous Organic Polymer for Rapid Scavenging of Oxoanions from Water

“…Furthermore, such porous polymers could also be manifested as an effective anion exchange material for the sequestration of pertechnetate (TcO 4 − ) ion, which is similar in size to permanganate but highly toxic due to its radioactive nature. [ 12–15 ]…”

“…Furthermore, such porous polymers could also be manifested as an effective anion exchange material for the sequestration of pertechnetate (TcO 4 − ) ion, which is similar in size to permanganate but highly toxic due to its radioactive nature. [12][13][14][15] The high mobility and water solubility of these oxoanions are major bottlenecks for their selective removal from wastewater. Various physical and chemical techniques, including ion exchange, electrodialysis, nanofiltration, and chemical precipitation, have been employed for sequestering oxoanions from wastewater.…”