Easily Recycled Porous Microparticles Prepared via Electrohydrodynamic Atomization for Selective Uranium Extraction with High Capacity

Abstract

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.

Porous Microparticle Preparation via Tuning Electrostatic Breakup Characteristics of a Non-Newtonian Fluid for High-Performance Uranium Extraction

“…PAO was successfully synthesized by the ammonia oximization reaction of PAN based on the reported method, as shown in Figure S1a. 27 Both PAO (10 mg mL −1 ) and SA (10 mg mL −1 ) were dissolved in a 0.1 M NaOH solution at 80 °C with gentle stirring for 2 h to produce the PAO/SA precursor (a transparent yellowish solution). The resulting PAO/SA precursor was used to prepare the PAO/SA CMPs directly via the EHDA technique.…”

“…The fact that n < 1 suggests that the PAO/SA precursor is a non-Newtonian fluid with shear thinning behavior. 27 2.3. Preparation for the PAO/SA CMPs.…”

“…Size-Dependent Uranium Adsorption. In the previous publication, 27 we investigated the adsorption kinetics, adsorption isotherms, adsorption selectivity, the desorption and regeneration characteristics of the material, as well as its adsorption mechanism.…”

“…Due to its fast and efficient operation, relatively low cost, and the ability to accurately control the droplet size, the EHDA technique is suitable for mass production of functional adsorbent particles. 26 In our recent publication, 27 the polyamidoxime (PAO)/SA composite microparticles (PAO/SA CMPs) were efficiently prepared using the EHDA technique. The PAO/SA CMPs showed superior uranium extraction performance, preeminent uranium selectivity, and antimicrobial properties, which can be readily recovered via sedimentation.…”

“…In our recent publication, the polyamidoxime (PAO)/SA composite microparticles (PAO/SA CMPs) were efficiently prepared using the EHDA technique. The PAO/SA CMPs showed superior uranium extraction performance, preeminent uranium selectivity, and antimicrobial properties, which can be readily recovered via sedimentation.…”