Bio-removal of uranium by the treated biosorbent from aqueous solutions as an efficient strategy in uranium bioremediation

The aim of this study was to evaluate the ability of treated Azolla filiculoides to uranium biosorption as a new biosorbent. In this study, uranium biosorption experiments were performed by untreated biomass and [Fe(CN)6]4--treated biomass and H2O2/MgCl2-treated biomass. Studies showed that the maximum uranium uptake capacity by various treated sorbents is pH 5. Freundlich isotherm was examined to evaluate the experimental data. The results showed that the treated sorbent with H2O2/MgCl2 is more efficient than other sorbents and its uranium adsorption is relatively rapid, reaching to the maximum in 60 minutes. Maximum uranium adsorption was obtained using the large adsorbent particles (2-4 mm). The maximum adsorption capacity of uranium ions by H2O2/MgCl2-treated sorbent under optimal conditions is about 42.2 mg /g dry biomass. The results showed that pretreatment can be a good way to increase the adsorption capacity of biosorbents.