Is <I>Sargassum</I> Amenable to Recover Uranium from Water in Nuclear Facilities

Abstract

The results reported in the present paper indicated that Sargassum sp. brown seaweed is amenable to contamination by Uranium under synthetic conditions, and probably in natural environments subject to water leakage from uranium facilities, although physico-chemical characteristics of each particular environment still must be addressed. Sargassum sp. biomass was used as biosorbent material for Uranium in batch conditions. Kinetic and equilibrium conditions were studied. Results obtained indicated that Sargassum sp. biomass reached equilibrium after 60 minutes of contact with a 1.0 mg/L and a 100.0 mg/L solution. The kinetic behavior observed indicated a 20-30% biosorption of Uranium in the first 20 minutes of process followed by a slower uptake up to 38% Uranium biosorption.The kinetic modeling of the process indicated that the less concentrated uranium solution fitted well to a second-order kinetic model, while the 100.0 mg/L solution fitted well both the first and second-order kinetic models. Those conclusions were reached based on the high correlation coefficients obtained. Equilibrium batch tests showed that uranium biosorption was equal, both after 1 hour and 3 hours of contact between the biomass and distinct Uranium solutions. Freundlich and Langmuir models were used to fit the experimental data. The Freundlich model best described Uranium biosorption, in comparison to the Langmuir model, based on higher correlation coefficients obtained.