Biosorption of Th4+ and UO
ions, both separately and in mixed equimolar ratio, was carried out using nitrate-buffered solutions of the cations at pH 1 in the presence of 5%w/w non-proliferative cell suspensions of Mycobacterium smegmatis. At equilibrium following a 3 h treatment, specific adsorption for 2 mM Th and U was, respectively, 102 and 115 mol g–1 dry biomass for individual solutions and 102 and 42 mol g–1 for the mixed 2/2 mM solution. Desorption studies of the cation-loaded biomass preparations in aqueous media and in soilbacterial suspensions within the pH range <1 to 11 showed that leaching of throium was generally less than 1% at pH 1–11 after 7 d, whereas uranium was leached to the extent of 2% at pH 1 and up to 10% under the same conditions in Th–U mixtures.
Authors:Y. Andrès, S. Redercher, C. Gerente, and G. Thouand
The biosorption capacities for cesium, technetium, uranium and nickel was determined. Various microbial strains, pH and mineral composition of medium (clay and concrete waters) were tested. For the cesium a column experiment with a biofilm was realised.