Abstract
Efficient sequestration of U(VI) from complex aqueous solution is of vital importance for environmental remediation. In this work, the fully phosphorylated graphene oxide foam (phos-GOF) was synthesized via a facile hydrothermal method and the as-prepared 3D phos-GOF was served as an adsorbent to capture U(VI) from aqueous solution. The introduction of abundant phosphorus-containing groups via phytic acid endows phos-GOF good hydrophilia and excellent affinity for U(VI). The adsorption performance of phos-GOF for U(VI) was carefully evaluated under different environments. phos-GOF shows rapid and high efficiency for U(VI) adsorption. The maximum adsorption capacity of phos-GOF for U(VI) is ∼483 mg/g, which is much higher than that of pristine graphene oxide foam (GOF). In addition, the spent 3D phos-GOF can be easily regenerated by a simple and low-cost desorption process using 0.02 mol/L HNO3. The interaction mechanism between phos-GOF and U(VI) is mainly attributed to the inner-sphere complexation between phosphoric functional groups and U(VI) based on a series of spectroscopic analyses. The 3D phos-GOF exhibits favorable sequestration performance towards U(VI) which can be used as a potential candidate in uranium-bearing wastewater treatment and disposal.
Fully phosphorylated 3D graphene oxide foam for the efficient removal of U(VI). [Display omitted]
•The free-standing 3D phos-GOF was prepared via simple and feasible hydrothermal method.•The maximum adsorption capacity of phos-GOF for U(VI) is ∼483 mg/g.•The adsorption of phos-GOF for U(VI) can be maintained at ∼ 93.5% after five cycles.•Inner-sphere complexation contributes much to the adsorption of phos-GOF towards U(VI).
The 3D phos-GOF exhibits rapid and high efficiency for U(VI) sequestration and can be easily separated and regenerated.