Enhanced arsenite removal from water using zirconium-ferrocene MOFs coupled with peroxymonosulfate:oxidation and multi-sites adsorption mechanism. (April 2023)

• Record Type: Journal Article
• Authors: Li, Zongchen; Ma, Shengjia; Sang, Linfeng; Qu, Guojuan; Zhang, Tao; Xu, Bin; Jin, Wei; Zhao, Yaping
• Is Part Of: Chemosphere. Volume 319(2023)
• Publication Date: 2023-04
• Subjects: Arsenite -- MOFs -- Ferrocene -- Multi-sites adsorption -- Oxidation; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2023.138044
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: The efficient removal of arsenite (As(III)) poses a significant challenge to traditional water treatment technologies due to its high toxicity and mobility. In this work, multifunctional Zirconium-Ferrocene Metal Organic Framework (ZrFc-MOF) fabricated with redox-active 1, 1-ferrocene dicarboxylic acid ligands and Zr 4+ precursors were elaborated to achieve remarkably enhanced As(III) removal via activation by peroxymonosulfate (PMS). The adsorption affinity coefficient increased from 0.097 to 2.035 L mg −1 and the maximum adsorption capacity increased from 59.79 to 111.34 mg g −1 compared with that without PMS. Besides the conventional homogeneous PMS oxidation and the following adsorption through Zr–O clusters of ZrFc-MOFs, the enhanced As(III) removal synergistic combines the oxidation mechanism of As(III) by reactive oxygen species (OH, S O 4 −, O 2 − and 1 O2 ) formed in Ferrocene (Fc) activating PMS process with the simultaneous formed extra adsorption sites of Ferrocenium (Fc + ). PMS also help ZrFc-MOF to avoid destruction in harsh alkaline condition, making the effluent in this advanced treatment meet the World Health Organization (WHO) threshold of 10 μg L −1 over a wide range of initial pH (2−11) with high selectivity and durability. These results indicate that this novel Fc-based MOFs activating PMS system has potential applicability for As(III) in oxidation and selectively capturing in the water environment. Graphical abstract: Zr-Fc MOFs and peroxymonosulfate (PMS) synergistically improve the As(III) removal, which can be attributed to the multi-site adsorption and heterogeneous catalytic oxidation mechanism originated from ferrocene ligands. Image 1 Highlights: ZrFc-MOF with multifunctional FcDA ligands was applied for As(III) synergistic oxidation and adsorption. FcDA ligands can act as heterogeneous catalytic sites for PMS activation which promoted As(III) oxidation. FcDA ligands can be simultaneously activated by PMS to be extra Fc + sites for total arsenic adsorption. ZrFc-MOF/PMS systems presented high As(III) removal efficiency, selectivity and durability.