Goyal N, Gao P, Wang Z, Cheng S, Ok YS, Li G, Liu L. Nanostructured chitosan/molecular sieve-4A an emergent material for the synergistic adsorption of radioactive major pollutants cesium and strontium.
JOURNAL OF HAZARDOUS MATERIALS 2020;
392:122494. [PMID:
32193120 DOI:
10.1016/j.jhazmat.2020.122494]
[Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 03/06/2020] [Accepted: 03/07/2020] [Indexed: 06/10/2023]
Abstract
A fresh adsorbent nanostructured chitosan/molecular sieve 4A hybrid (NSC@MS-4A) was fabricated for the rapid adsorption of strontium (Sr2+) and cesium (Cs+) ions from aqueous solutions. The as-obtained NSC@MS-4A were thoroughly characterized by XRD, FE-SEM, EDS, BET, XPS and FT-IR. The physio-chemical properties and structural aspects revealed that NSC@MS-4A acquires fine surface area (72 m2/g), porous structure as well as compatible functional groups (-P-O-P and -C-O-C) for the admission of Cs+ and Sr2+ ions. The batch adsorption studies concluded that prepared adsorbent displayed a maximum adsorption of 92-94 % within 40 min. Fast adsorption of Cs+ and Sr2+ was achieved at neutral pH (6-7), ambient temperature (25-30 °C) and slow agitation speed (50-60 rpm) which could propose vast benefits such as little power utilization and uncomplicated operation. Among six types of adsorption isotherms, Freundlich isotherm showed the best fit with R2>0.997. Pseudo-second order made a better agreement as compare to other kinetic models. The thermodynamic coefficients suggested the passage of Cs+ and Sr2+ ions through the liquid solid boundary is exothermic and spontaneous. The NSC@MS-4A displayed excellent regenerability properties over five repetitive adsorption/desorption cycles, which specified that as-obtained NSC@MS-4A is a sustainable as well as efficient adsorbent for practical decontamination of radioactive liquid waste.
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