A superparamagnetic ZnFe2O4@NH2-SiO2@PMDI@ dithizone microspheres as an effective selective adsorbent for Pb2+ from wastewater. Issue 1 (February 2019)

• Record Type: Journal Article
• Authors: Ma, Jie; Zeng, Yulan; Sun, Mengya; Zhang, Manman; Zheng, Weiguo; Zhang, Cuihong; Wang, Qingyang; Xiao, Yao; Zhang, Shuping
• Is Part Of: Journal of environmental chemical engineering. Volume 7:Issue 1(2019)
• Publication Date: 2019-02
• Subjects: PDMI -- Adsorption -- Nanocomposite -- Ferrite -- Lead ions -- Heavy metal; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2018.102874
• Languages: English
• ISSNs: 2213-2929

Abstract

Graphical abstract: Highlights: A paramagnetic ZnFe2 O4 nano-composite adsorbent is firstly constructed, and PMDI is in situ synthesized on the surface of nanocomposite. ZnFe2 O4 @NH2 -SiO2 @ PMDI @ dithizone microspheres as a novel nanoextractant has firstly been synthesized via a facile reliable solution procedure. The solid phase extractant presents an excellent speed and capacity for Pb 2+ from water. The extractant nanocomposites has an excellent reusability with EDTA as eluent. The extractant performs as a good specific extraction of Pb 2+ ions almost without interfered by common metal ions. Abstract: Herein, a paramagnetic multilayer ZnFe2 O4 @NH2 -SiO2 @PMDI@dithizone (ZNPD) nanocomposite microspheres were first devised and constructed via a series of solution processes, and polydiphenylmethane diisocyanate (PMDI) is in situ synthesized and coated on the surface of ZnFe2 O4 @NH2 -SiO2 . The nanocomposites were used to absorb Pb 2+ ions from dilute solutions prior to a determination by FAAS. Some critical parameters about adsorption properties of the as-prepared ZNPD nanocomposite microspheres were investigated, including influence the initial concentration of Pb 2+, solution pH, the dose of absorbents, the reusability. The results show that the synthesized nano-adsorbent present wide acidic resistance, excellent adsorption capacity and sorption/desorption speed, facile separability, and admirable reusability. The adsorption capacity of the absorbents was 267.2 mg/g, and the adsorption equilibrium finishes in 10 min. Pb 2+ ions are almost desorbed from the extractant by a given EDTA solution in 20 min. Its adsorption capacity is hardly loss after six times of adsorption-regeneration cycles.