Using fly ash treated by NaOH and H2SO4 solutions for Hg2+ and Cd2+ ion adsorption.

Nguyen Thuy Chinh, Tran Thi Mai, Nguyen Thi Thu Trang, Nguyen Thi Thanh Huong, Thai Hoang


This paper presents the results of adsorption ability of heavy metal ions (Hg2+ and Cd2+) by fly ash (FA) before and after treatment using NaOH and H2SO4 solutions.  Original- and treated FA were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Scanning Electron Microscope (SEM). Specific surface area of FA before and after treatment was calculated by Brunauer – Emmett – Teller (BET) isotherm equation. The obtained results indicated that the morphology and specific surface area of FA changed clearly after treatment by acid or alkaline solutions. Adsorption capacity the Hg2+ and Cd2+ ion by FA was determined from data of UV-Vis spectra. After treatment, the adsorption capacity of ions by FA increased remarkably in comparison with non-treated FA. The FA treated by NaOH solution has the adsorption capacity higher than FA treated by H2SO4 solution. The maximum adsorption capacity of the FA treated by NaOH solution for Cd2+ and Hg2+ ions at room temperature is 28.97 and 14.60 mg/g, respectively. The equilibrium adsorption data were described by the Langmuir and Freundlich isotherm models. The results showed that equilibrium data were fitted well to the Langmuir isotherm.

Keywords. Fly ash, treatment, adsorption capacity, heavy metal, Langmuir isotherm.


Fly ash, treatment, adsorption capacity, heavy metal, Langmuir isotherm

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Kim TY, Park SK, Cho SY, Kim HB. Sorption of heavy metals by brewery biomass, Korean J. Chem Eng, 22, 91-8 (2005).

M. Q. Jiang, X. Y. Jin, X. Q. Lu, Z. L. Chen. Adsorption of Pb(II), Cd(II), Ni(II) and Cu(II)onto natural kaolinite clay, Desalination, 252, 33-39 (2010).

C. Green-Ruiz. Adsorption of mercury(II) from aqueous solutions by the clay mineral montmorillonite, Bull. Environ. Contam. Toxicol., 75, 1137-1142 (2005).

Maria Visa, Andreea-Maria Chelaru. Hydrothermally modified fly ash for heavy metals and dyes removal in advanced wastewater treatment, Applied Surface Science, 303, 14-22 (2014).

Y. N. Mata, M. L. Blázquez, A. Ballester, F. González, J. A. Mu˜noz. Sugar beet pulp pectin gels as biosorbent for heavy metals: preparation and determination of biosorption and desorption characteristics, Chem. Eng. J., 150, 289-301 (2009).

D. Mohan, P. K. Singh. Single and multicomponent adsorption of cadmium and zinc using activated carbon derived from bagasse - an agricultural waste, Water Res., 36, 2304-2318 (2002).

S. Wang, T. Terdkiatburana, M. O. Tadé. Single and co-adsorption of heavy metals on humic acid, Sep. Purif. Technol., 58, 353-358 (2008).

Jian Zhao, Man-Chao He. Theoretical study of heavy

metal Cd, Cu, Hg, and Ni(II) adsorption on the kaolinite (0 0 1) surface, Applied Surface Science, 317, 718-723 (2014).

M. Visa, A. Duta. Methyl-orange and cadmium simultaneous removal using fly ash and photo-Fenton systems, J. Hazard. Mater., 244, 773-779 (2013).

Ta Ngoc Don, Vo Thi Lien. Zeolite from fly ash: Synthesis, characteristics and application. II. Study on the derive of fly ash to product containing P1 zeolite, Journal of Chemistry and Applications, 3, 24-27 (2005).

Le Thanh Son, Tran Kong Tau. Treatment of fly ash for soil improvement absorbing material, Journal of Soil Science, 5, 64-68 (2001).

Maria Visa, Luminita Isac, Anca Duta. Fly ash adsorbents for multi-cation wastewater treatment, Applied Surface Science, 258, 6345-6352 (2012).

I. Grigorios, K. Athanasios, K. Nikolaos, V. Charalampos. Zeolite development from fly ash and utilization in lignite mine-water treatment, International Journal of Mineral Processing, 139, 43-50 (2015).

Atomic Radius of the elements,

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