[Influence of Calcium Ion Pre-treatment on Phosphate Adsorption onto Magnetic Zirconium/Iron-modified Bentonite].
Huan Jing Ke Xue
; 40(2): 658-668, 2019 Feb 08.
Article
em Zh
| MEDLINE
| ID: mdl-30628328
ABSTRACT
Two kinds of magnetic zirconium/iron-modified bentonites (ZrFeBTs), including magnetic zirconium/iron modified raw bentonite (ZrFeRBT) and magnetic zirconium/iron-modified Ca2+-pretreated bentonite, (ZrFeCaBT) were prepared and characterized. Their phosphate adsorption characteristics were compared to determine the effect of the Ca2+ pre-treatment on the adsorption of phosphate onto ZrFeBTs. The results showed that the as-prepared ZrFeBTs contained Fe3O4 and Zr, and the content of exchangeable Ca2+ in ZrFeCaBT was much higher than that in ZrFeRBT. The adsorption isotherm data exhibited good agreement with the Langmuir isotherm model, with maximum monolayer phosphate adsorption capacities of 8.70 mg·g-1 and 11.5 mg·g-1 for ZrFeRBT and ZrFeCaBT, respectively. The isotherm and kinetics studies showed that the adsorption of phosphate on ZrFeBTs was a chemisorption process. The phosphate adsorption capacities for ZrFeBTs decreased with increasing solution pH. The ZrFeBTs exhibited a high selective adsorption for phosphate in the presence of anions and cations, including Cl-, HCO3-, SO42-, NO3-, Na+, K+, Mg2+, and Ca2+. Furthermore, coexisting Ca2+ greatly enhanced the adsorption of phosphate onto ZrFeBTs. The pre-treatment of raw bentonite with Ca2+ significantly improved the adsorption of phosphate onto ZrFeBTs.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Tipo de estudo:
Prognostic_studies
Idioma:
Zh
Revista:
Huan Jing Ke Xue
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
China