Indexed by:
Abstract:
Radionickel ion (Ni-63(2+)) remediation is critical for public health and the environment, but selectively capturing of Ni2+ from complex environments like seawater presents a challenge. Metal sulfide ion exchangers (MSIEs) are emerging as efficient adsorbents for radionuclides; however, the study of MSIEs for selectively removing Ni2+ is still in its infancy. Herein, the layered metal sulfide K2Cu2Sn2S6 (CTS-1) with a unique sandwich-like anionic framework was synthesized by the hydrothermal method for the first time, representing a novel approach in the selective capture of Ni2+ from complex environments. Single-crystal structural analysis confirmed the sandwich-like framework, in which a [Cu-S] sublayer is sandwiched by two [Sn-S] sublayers with parallel grooves. The charge-balancing K+ ions are located within these grooves. Due to its special structure, CTS-1 exhibits remarkable adsorption capacities for Ni2+ with rapid kinetics (a high rate constant k(2) of 7.26 x10(-2) g/(mgmin)), broad pH durability (removal rates >97 % at pH 3-12), and high selectivity (separation factors for Ni2+ >700 against various cations). Impressively, it can efficiently remove Ni2+ from multiple complex environments, achieving a 90.28 % removal rate even in seawater (C-0(Ni) similar to 5 mg/L). CTS-1 is environmentally friendly and suitable for use in fixed-bed columns for the practical application. Moreover, Ni2+ ions are captured through ion exchange with K+, and the high selectivity stems from the strong affinity of S2- for Ni2+ and the trapping effect of the grooves within the structure. In summary, this pioneering study demonstrates the highly selective capture of Ni2+ by a sandwich-like layered MSIE, potentially inspiring the development of efficient scavengers for radionuclides.
Keyword:
Reprint 's Address:
Email:
Version:
Source :
JOURNAL OF HAZARDOUS MATERIALS
ISSN: 0304-3894
Year: 2025
Volume: 482
1 2 . 2 0 0
JCR@2023