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

Effective recovery of uranium from wastewater has positive significance to environmental treatment and the development of the nuclear industry. Through electrospinning technology, the ternary layered double hydroxide (NiFeAl-LDHs), polyvinyl alcohol (PVA) and polyacrylic acid (PAA) was used as the precursor solution to produce NiFeAl-LDHs/PVA/PAA composite nanofibers, and it can adsorb uranium under weak acid conditions. The material structure and character of the prepared fiber were analyzed by SEM, FT-IR, XRD and XPS, besides the various factors on the adsorption of uranium by the fiber under static adsorption were studied. The adsorption process of NiFeAl-LDHs/PVA/PAA to U(VI) conformed to the pseudo-second-order model (R2 > 0.998). The maximum theoretical adsorption capacity of U(VI) on NiFeAl-LDHs/PVA/PAA was 203.32 mg/g at pH 6.0 calculated by the Langmuir model. The value of thermodynamic parameters showed that the adsorption process of uranium on NiFeAl-LDHs/PVA/PAA was endothermic and spontaneous. NiFeAl-LDHs/PVA/PAA can still effectively adsorb uranium after passing five adsorption–desorption cycle tests. Therefore, NiFeAl-LDHs/PVA/PAA was expected to be used in practical applications to treat uranium-containing wastewater.