Original scientific paper

https://doi.org/10.5562/cca2646

Removal of Copper(II) and Zinc(II) Ions From Aqueous Solution by Chemical Treatment of Coal Fly Ash

Eleonora Sočo orcid.org/0000-0003-0658-5049 ; Department of Inorganic and Analytical Chemistry, Faculty of Chemistry, Rzeszów University of Technology, 6 Powstańców Warszawy Ave., PL-959 Rzeszów, Poland
Jan Kalembkiewicz ; Department of Inorganic and Analytical Chemistry, Faculty of Chemistry, Rzeszów University of Technology, 6 Powstańców Warszawy Ave., PL-959 Rzeszów, Poland

Abstract

The aim of this study was to investigate the chemical modifications of coal fly ash (CFA) treated with HNO3 or ammonium acetate (AcNH₄) or NaOH or sodium diethyldithiocarbamate (NaDDTC) as an adsorbent for the removal of copper(II) and zinc(II) ions from aqueous solution. The morphology of fly ash grains before and after modification was examined via X-ray diffraction (XRD) and images of scanning electron microscope (SEM). Adsorption of copper(II) and zinc(II) ions was conducted under batch process at different duration, concentrations and temperature of the suspension. Equilibrium experiments shows that the selectivity of CFA-NaOH nanoparticles towards Cu(II) ions is greater than that of Zn(II) ions, which is related to their hydrated ionic radius and first hydrolysis equilibrium constant. The adsorption isotherms were described by Langmuir and Freundlich models. Kinetic data revealed that the adsorption fits well by the pseudo-second-order rate model with high regression coefficients. Thermodynamic parameters suggested that the immobilization Cu(II) and Zn(II) ions onto CFA-NaOH is a spontaneous process. Results demonstrated that the treating coal fly ash with alkaline solution was a promising way to enhance Cu(II) and Zn(II) ions adsorption.

Keywords

kinetic and thermodynamic adsorption; coal fly ash; copper and zinc; scanning electron microscopy; X-ray diffraction

Hrčak ID:

150532

URI

https://hrcak.srce.hr/150532

Publication date:

30.12.2015.

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