Evaluating the use of activated carbon felts to remove Co2+,Ni2+ and Sr2+ from wastewater
Résumé
As a result of numerous advantages such as high surface areas, rapid sorption rates and lowhydrodynamic resistances, activated carbon felts (ACF) are interesting materials for applications inwastewater treatment. This paper studies the use of a polyacrylic acid grafted and a non grafted ACF inthe sorption of Co2+, Ni2+ and Sr2+ from a synthetic solution (high NaNO3 concentration) representing anuclear wastewater. Scanning electron microscopy and surface area analysis were employed tophysically characterize bothmaterials. Experimental results for the sorption of ternary mixtures allowedus to uncover a selectivity among the three cations that could not be deducted directly from the sorptionisotherms of individual cations. In all cases, differences in the sorption capacity could be related to theelectronegativity of the metal cations. Complementarily, removal of Co2+, Ni2+ and Sr2+ by a fixed bedcolumn containing non grafted ACF was studied by means of monoelement and ternary sorptionexperiments. Only breakthrough curves of individual metals could be fitted by the Thomas model.Overshot of Sr2+ and Co2+ was observed on ternary sorption experiments. The set of results obtainedindicate that ACF can potentially be employed in the treatment of nuclear effluents where a selectiveseparation of Sr2+ from Ni2+ and Co2+ is required.