Design of hybrid goethite nanocomposites as potential sorbents for lanthanum from aqueous media

ABSTRACT

Nano-goethite (NG) was synthesized using a co-precipitation method, where the surface of NG was modified by composite formation with activated carbon and sodium alginate, respectively, to increase adsorption capacity. The adsorption process of La(III) was optimized at defined conditions: pH 5.0, contact time 6.0 h, sorbent dosage (0.1 g/20 ml) and an initial La³⁺concentration (500 ppm). The maximum La(III) adsorption capacity (mg/g) was determined using the Sips model, as follows: pristine NG (49.5), activated carbon modified goethite: GAC-2 (44.0) and GAC-1 (56.8), and sodium alginate modified goethite: GSA-1 (63.9) and GSA-2 (77.8). The kinetic uptake profiles of La³⁺ were described by pseudo first order model. The sorbents can be classified according to their relative adsorption capacity, as follows: GSA-2 > GSA-1 > GAC-1 > NG > GAC-2.

KEYWORDS:

• Nano-goethite
• activated carbon
• sodium alginate
• lanthanum
• adsorption

Acknowledgements

M. A. Sayed is grateful to the Egyptian government (Cultural Affairs and Mission Sector) for funding this research and also for the collaborative research opportunity as visiting research student at the University of Saskatchewan. LDW acknowledges the support provided by the Natural Sciences and Engineering Research Council of Canada (NSERC), Discovery Grant (RGPIN 2016-06197).

Declaration of interest

The authors declare none.

Supplementary material

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