Constructing new Fe3O4@MnOx with 3D hollow structure for efficient recovery of uranium from simulated seawater. (November 2021)

• Record Type: Journal Article
• Authors: Zhang, Tingting; Chen, Jiemin; Xiong, Huiyan; Yuan, Zongdi; Zhu, Yuling; Hu, Baowei
• Is Part Of: Chemosphere. Volume 283(2021)
• Publication Date: 2021-11
• Subjects: Uranium -- Fe3O4@MnOx -- Sorption -- Seawater; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.131241
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Enrichment of uranium from seawater is a promising method for addressing the energy crisis. Current technologies are generally not effective for enriching uranium from seawater because its concentration in seawater is low. In this study, new Fe3 O4 @MnO x with 3D hollow structure, which is capable of enriching low concentration uranium, was prepared via a novel redox etching method. The physicochemical characteristics of Fe3 O4 @MnO x were studied with TEM, HRTEM, SEAD, FTIR, XRD, and N2 adsorption-desorption analysis. Dynamic kinetic studies of different initial U(VI) concentrations revealed that the pseudo-second-order model fit the sorption process better, and the sorption rates of Fe3 O4 @MnO x in 1, 10, and 25 mg/L U(VI) solution were 0.0124, 0.00298, and 0.000867 g/mg·min, respectively. Isothermal studies showed that the maximum sorption amounts were 50.09, 56.27, and 64.62 mg/g for 1, 10, and 25 mg/L U(VI), respectively, at pH 5.0 and 313 K, suggesting that Fe3 O4 @MnO x could effectively enrich low concentration U(VI) from water. The sorption amount of U(VI) did not significantly decrease in the presence of Na +, Mg 2+, and Ca 2+ . HRTEM, FTIR, and XPS results demonstrated that Fe(II) and Mn/Fe–O–H active sites in Fe3 O4 @MnO x were accounted for the high and specific enrichment efficiency. A column experiment was conducted to evaluate the U(VI) sorption efficiency of Fe3 O4 @MnO x in simulated seawater. The U(VI) sorption efficiency remained above 80% in 28 days run. Our findings demonstrate that Fe3 O4 @MnO x has extraordinary potential for the enrichment of uranium from simulated seawater. Graphical abstract: Image 1 Highlights: Fe3 O4 @MnO x was constructed via a novel self-sacrifice template method. Fe3 O4 @MnO x exhibited 3D hollow structure and Mn/Fe–O–H active sites. Fe3O4@MnO x showed excellent sorption capacity for low concentration U(VI). U(VI) was mainly enriched in the forms of UO2 and Mn/Fe-O-UO2 2+ . The U(VI) sorption rate remained above 80% with simulated seawater.