Adsorption of arsenite and selenite using an inorganic ion exchanger based on Fe-Mn hydrous oxide. J Colloid Interface Sci

Department of Earth Sciences-Geochemistry, Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3508 TA Utrecht, The Netherlands.
Journal of Colloid and Interface Science (Impact Factor: 3.37). 09/2011; 365(1):213-21. DOI: 10.1016/j.jcis.2011.09.023
Source: PubMed


The adsorption behaviour and mechanism of As(III) and Se(IV) oxyanion uptake using a mixed inorganic adsorbent were studied. The novel adsorbent, based on Fe(III)-Mn(III) hydrous oxides and manganese(II) carbonate, was synthesised using a hydrothermal precipitation approach in the presence of urea. The inorganic ion exchanger exhibited a high selectivity and adsorptive capacity towards As(III) (up to 47.6 mg/g) and Se(IV) (up to 29.0 mg/g), even at low equilibrium concentration. Although pH effects were typical for anionic species (i.e., the adsorption decreased upon pH increase), Se(IV) was more sensitive to pH changes than As(III). The rates of adsorption of both oxyanions were high. Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) studies showed that the ion exchange adsorption of both anions took place via OH(-) groups, mainly from Fe(III) but also Mn(III) hydrous oxides. MnCO(3) did not contribute directly to As(III) and Se(IV) removal. A higher adsorptive capacity of the developed material towards As(III) was partly due to partial As(III) oxidation during adsorption.

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    • "Various inorganic materials have been successfully used for the removal of arsenic and fluoride from water/waste water. Several workers have used hydrous metal oxides (HMOs) for removing different types of inorganic anions like arsenic (Li et al. 2012; Luther et al. 2012; Szlachta et al. 2012) and fluoride (Viswanathan and Meenakshi 2010; Mohapatra et al. 2012; Montoya et al. 2012; Mourabet et al. 2012) from aqueous solutions. Nitrate removal from water by adsorbents such as nano-alumina (Bhatnagar et al. 2010) and hydrous bismuth oxide (Singh and Ghosh 2000; Singh et al. 2012) have been reported by a few workers. "
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