Efficient uranium electrochemical deposition with a functional phytic Acid-Doped Polyaniline/Graphite sheet electrode by Adsorption-electrodeposition strategy

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2023-02, Vol.457, p.141221, Article 141221
• Main Authors: Huang, Mengnan, Xie, Lisha, Wang, Yuejiao, He, Hongjiang, Yu, Haibiao, Cui, Junshuo, Feng, Xiaogeng, Lou, Zhenning, Xiong, Ying
• Format: Article
• Language: English
• Subjects: Electrodeposition; Extraction; Phytic acid; Polyaniline; Uranium
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2022.141221

[Display omitted] •PA activates and brings conductivity, hydrophilicity and affinity for UO22+ to PANI.•Green, low energy and cheap process suitable for large-scale industrial production.•Reduce the concentration of spiked seawater from 3 mg/L to 29 ug/L within 36 h.•The final product is uranium precipitate, which is easy to collect.•Re-adsorption of waste electrodes for maximum economical and performance utilization. The extraction of uranium is critical because it is an essential radioactive element for sustainable fuel supply. Herein, a phytic acid-doped polyaniline/graphite sheet (PA-PANI/GS) electrode is demonstrated for efficient uranium extraction from aqueous solutions by adsorption-electrodeposition strategy. The doping of phytic acid activates conductivity to intrinsic polyaniline, brings hydrophilicity and offers surface-specific binding sites for uranyl ions. The phosphate groups released from the PA-PANI/GS surface, the high electron transfer on the polyaniline chain, and the presence of Na+ allow the formation of (UO2)3(PO4)2, (UO2)3(PO4)2·4.8H2O and Na2O(UO3·H2O)x precipitates during electrochemical deposition, which can easily be collected. The extraction capacity for uranium with the PA-PANI/GS is 1058 mg/g without reaching saturation. The reduction of the uranium concentration in spiked seawater from 3 mg/L to 29 ug/L is achieved with an extraction amount of about 266 ug within 36 h, which is below the US Environmental Protection Agency uranium limits for drinking water (30 ug/L). The PA-PANI/GS electrode after deposition cycles still recover more than 82 % of uranium through the “3 + 1” mode of physicochemical adsorption, which achieve maximum utilization in performance and economy. Low-energy of extraction processes and low-cost of electrode synthesis have many advantages in large-scale industrial applications.