Facile immobilization of NiFeAl-LDHs into electrospun poly(vinyl alcohol)/poly(acrylic acid) nanofibers for uranium adsorption

Phosphorylated hollow carbon-based material derived from ZIF-8 and its U(VI) adsorptive performance

Inspired by its large specific surface area, and tunable chemical and physical properties, a hollow carbon-based mater8ial derived from ZIF-8 with phosphate groups (HCM-PO4) was prepared for the elimination of U(VI). The structural and surface features of HCM and HCM-PO4 were thoroughly examined using techniques such as SEM, TEM, and XRD. The resulting carbon material, HCM-PO4, exhibits a higher BET surface area of 571.2 m2·g-1, featuring a hollow structure. The removal procedure of HCM-PO4 for U(VI) aligns with the quasi-secondary kinetic model. Furthermore, the theoretical sorption capacity of HCM-PO4 was found to be 482.30 mg·g-1 at 298.15 K. The results obtained from XPS, FT-IR, and EDS analysis of HCM-PO4 after adsorption revealed the coordination of the phosphate group for U(VI), contributing significantly to the adsorption process. In brief, the HCM-PO4 demonstrates excellent adsorptive ability, positioning it as a hopeful expectant to remove U(VI) from wastewater.

Phytic acid-modified carboxymethyl cellulose hydrogel for uranium adsorption from aqueous solutions

Phytic acid-modified carboxymethyl cellulose (CMC-PA) has been investigated as a promising adsorbent for the removal of uranium from aqueous solutions. The synthesis of CMC-PA involves the hydrogen bonding interaction between CMC and PA, resulting in the incorporation of PA groups onto the cellulose backbone. The hydrophilicity, reusability and adsorption capacity of the prepared CMC-PA hydrogel have improved with the increase of PA content. Moreover, the adsorption experiments were conducted by varying parameters such as pH, initial uranium concentration, and contact time. The results showed that CMC-PA exhibited excellent uranium adsorption performance, with a theoretical maximum adsorption capacity of 436 mg/g. In addition, the material exhibits excellent reusability, and the reusability improves with the increase of crosslinking density, indicating that the crosslinking structure of the polymer gel can effectively enhance the structural stability of the material. Furthermore, CMC-PA also exhibits high selective adsorption performance towards uranium ions in the presence of various competing ions. Its high adsorption capacity, reusability, and selectivity make it a promising candidate for high-performance uranium ion adsorbents.

Boron nitride decorated poly(vinyl alcohol)/poly(acrylic acid) composite nanofibers: A promising material for biomedical applications

In this study, polyvinyl alcohol (PVA) and polyacrylic acid (PAA) nanofibers loaded with boron nitride nanoparticles (mBN) were fabricated by using electrospinning and crosslinked by heat treatment. The physical, chemical, and mechanical properties, hydrophilic behavior, and degradability of composite nanofibers were evaluated. The mechanical properties such as elastic modulus, elongation percentage at the break, and mechanical strength of PVA/PAA nanofibers improved with mBN loading. The thermal conductivity of composite nanofibers reached 0.12 W/m·K at mBN content of 1.0 wt% due to the continuous heat conduction pathways of mBN. In the meantime, while there was no cytotoxicity recorded for both L929 and HUVEC cell lines for all composite nanofibers, the antimicrobial efficiency improved with the incorporation of mBN compared with PVA/PAA and recorded as 68.8% and 75.1% for Escherichia coli and Staphylococcus aureus, respectively. On this basis, the present work proposes a promising biomaterial for biomedical applications such as dual drug delivery, particularly including both hydrophobic and hydrophilic drugs or wound dressing.