The
current study explores the potential of combining the electrohydrodynamic
atomization (EHDA) technique with high-performance uranium extraction
for the first time, where composite microparticles (CPs) were facilely
prepared via the EHDA technique, with the particle size being precisely
controlled. The precursor is made of an environmentally friendly aqueous
solution of polyamidoxime and sodium alginate. Key parameters for
controlling droplet size and generation frequency were determined.
The generated microdroplets were collected via a coagulating bath,
while transforming the droplets into hydrogel particles. The hydrogel
particles were found to be uniform in size (197.1 ± 13.3 μm),
with an ultrahigh generating frequency of ∼400 Hz, indicating
the formation of 1.44 × 106 particles per hour. The
CPs were then obtained after freeze-drying, which were characterized
to be a hollow structure, with interpenetrating nanopores being observed
inside the particle shell. The CPs showed superior uranium extraction
performance (maximum uranium adsorption capacity of 1497.4 mg g–1 at 298 K), pre-eminent uranium selectivity, and antimicrobial
properties, which can be readily recovered via sedimentation. This
work offers a novel route for generating high-performance uranium
adsorbents with controllable size, in a high-efficient, facile, and
low-cost way, which shows great potential for sustainable uranium
extraction in a commercial scale.