A high-efficient and recyclable aged nanoscale zero-valent iron compound for V5+ removal from wastewater: Characterization, performance and mechanism. (September 2022)

• Record Type: Journal Article
• Authors: Liu, Tingyi; Wang, Peng; Wang, Zhong-Liang
• Is Part Of: Chemosphere. Volume 302(2022)
• Publication Date: 2022-09
• Subjects: Nanoscale zero-valent iron -- UIO-66 (Zr–O) -- Vanadium -- Mechanism -- Recyclability; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2022.134833
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: An effective complex of nanoscale zero-valent iron (NZVI) supported on zirconium 1, 4-dicarboxybenzene metals-organic frameworks (UIO-66) with strong oxidation resistance was synthesized (NZVI@UIO-66) for V 5+ removal from wastewater. The results demonstrated that NZVI was successfully loaded on UIO-66 with a uniform dispersion, and then the composite was aged in the air which was named A-NZVI@UIO-66. V 5+ could be removed quickly and completely using A-NZVI@UIO-66 in a wider pH range except for the pH = 1 condition. The reaction between A-NZVI@UIO-66 and V 5+ was an endothermic process. Freundlich model with a better-fitted value showed the adsorption of V 5+ on A-NZVI@UIO-66 was multi-layer heterogeneous adsorption and the adsorbed amount of V 5+ was 397.23 mg V/g NZVI. Nitrate had a competitive inhibition on V 5+ removal by A-NZVI@UIO-66. Mechanisms of vanadium elimination from the aqueous phase by A-NZVI@UIO-66 included physical adsorption, reduction, and complex co-precipitation, particularly the reduction dominated. The subsistent Zr–O bond in A-NZVI@UIO-66 provided a possible double reaction path by playing an electron donor, storage, or conductor role. After acid leaching, A-NZVI@UIO-66 represented good reusability in the removal of V 5+ from the practical mine sewage. Graphical abstract: Image 1 Highlights: NZVI@UIO-66 synthesized prevents NZVI from aggregation successfully. V 5+ can be removed efficiently and quickly in different conditions. The removal mechanism is mainly based on adsorption and reduction. The composite is with good reusability in the practical application. The subsistent Zr–O bond provide a possible double reaction path.