A superfast hexavalent chromium scavenger: Magnetic nanocarbon bridged nanomagnetite network with excellent recyclability

Xiaojiang Xu; Hongyuan Zhang; Chao Ma; Hongbo Gu; Han Lou; Shangyun Lyu; Chaobo Liang; Jie Kong; Junwei Gu

doi:10.1016/j.jhazmat.2018.03.059

A superfast hexavalent chromium scavenger: Magnetic nanocarbon bridged nanomagnetite network with excellent recyclability

J Hazard Mater. 2018 Jul 5:353:166-172. doi: 10.1016/j.jhazmat.2018.03.059. Epub 2018 Apr 10.

Authors

Xiaojiang Xu¹, Hongyuan Zhang¹, Chao Ma¹, Hongbo Gu², Han Lou¹, Shangyun Lyu¹, Chaobo Liang³, Jie Kong⁴, Junwei Gu⁵

Affiliations

¹ Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai 200092, PR China.
² Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai 200092, PR China. Electronic address: hongbogu2014@tongji.edu.cn.
³ MOE Key Laboratory of Space Applied Physics and Chemistry, Shaanxi Key Laboratory of Macromolecular Science and Technology, Department of Applied Chemistry, School of Science, Northwestern Polytechnical University, Xi' an, Shaanxi, 710072, PR China.
⁴ MOE Key Laboratory of Space Applied Physics and Chemistry, Shaanxi Key Laboratory of Macromolecular Science and Technology, Department of Applied Chemistry, School of Science, Northwestern Polytechnical University, Xi' an, Shaanxi, 710072, PR China. Electronic address: kongjie@nwpu.edu.cn.
⁵ MOE Key Laboratory of Space Applied Physics and Chemistry, Shaanxi Key Laboratory of Macromolecular Science and Technology, Department of Applied Chemistry, School of Science, Northwestern Polytechnical University, Xi' an, Shaanxi, 710072, PR China. Electronic address: gjw@nwpu.edu.cn.

PMID: 29674091
DOI: 10.1016/j.jhazmat.2018.03.059

Abstract

In this work, a nanocarbon bridged nanomagnetite network (NC-NMN) is developed through the electrospinning of epichlorohydrin functionalized polystyrene (f-PS), followed by the direct calcination of f-PS and ferric nitrate, which is capable of superfast removing hexavalent chromium (Cr(VI)) from polluted water within only 15 s benefiting from its gridding framework, with an adsorption rate constant of 1.64 g mg^-1 min^-1 according to the pseudo-second-order kinetics. The well-fitted Langmuir isotherm model indicates a monolayer adsorption for Cr(VI) on NC-NMN. The thermodynamic parameters including negative ΔG° and positive ΔH° demonstrate that the Cr(VI) adsorption on NC-NMN is spontaneous and endothermic. The Cr(VI) adsorption retention, which is only 3.8%, is achieved for NC-NMN after five cycles, exhibiting a prominent stability and an excellent recyclability. X-ray photoelectron spectroscopy (XPS), zeta potential and energy-filter transmission electron spectroscopy (EFTEM) results illustrate that both the electrostatic attraction and the network structure of NC-NMN are responsible for the superior Cr(VI) adsorption performance. This work intends to provide a new method for designing the novel structure materials for polluted water treatment.

Keywords: Adsorption; Hexavalent chromium; Magnetic; Nanocarbon bridged nanomagnetite; Recyclability.