1 research outputs found
Hierarchical Self-Assembled Polyimide Microspheres Functionalized with Amidoxime Groups for Uranium-Containing Wastewater Remediation
Through molecule self-assembly and subsequent surface
functionalization,
novel uranium adsorbent AO–OB hierarchical self-assembled polyimide
microspheres (AO-OBHSPIMs) were obtained by introducing the amidoxime
groups into hierarchical self-assembled polyimide microspheres for
the efficient and selective recovery of uranium from wastewater. The
results of Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron
spectroscopy (XPS), scanning electron microscopy (SEM), X-ray diffraction
(XRD), and nitrogen adsorption–desorption isotherm showed that
AO-OBHSPIMs were a semicrystalline polymer material with self-supporting
hierarchical structure and low pore volume, and they were equipped
with abundant amidoxime groups. Given the recognized selectivity of
amidoxime groups and their hierarchical structure, AO-OBHSPIMs exhibited
excellent selectivity to uranyl ions. Moreover, AO-OBHSPIMs exhibited
good stability and recyclability and remarkable removal percentage
within low-concentration solution (99.4%) and simulated uranium-containing
wastewater (97.3%). AO-OBHSPIMs could be applied to fixed-bed column
adsorption due to their large particle size and self-supporting hierarchical
structure that can facilitate water flow. The in-depth discussion
of the adsorption mechanism showed that the adsorption mainly depended
on the combined action of electrostatic interactions and complexation,
and the adsorption process was a spontaneous endothermic monolayer
adsorption. In summary, AO-OBHSPIMs exhibited good application prospects
in uranium-containing wastewater remediation